Technical Discussions

Microsoft Silverlight

noreply@blogger.com (nandun) — Mon, 27 Dec 2010 05:08:00 +0000

Microsoft Silverlight is the new product they introduced for rich interactive web application developments. In previous topics I introduced how you can use Ajax technologies for rich web application development. We use Ajax technologies to introduce JavaScript and call server calls through JavaScript to minimize page refresh. With this method we can save lot of page refreshes but we might face some difficulties in developing Ajax enable applications when we go for complex applications. Silverlight is a powerful development platform for creating engaging, interactive user experiences for Web, desktop, and mobile applications when online or offline. With Silverlight you can build web or mobile applications very similar to desktop application developments. You know that we have much more freedom with desktop application to use complex controls. But with web application we have some limitations due to the technologies use, bandwidth, security issues...etc. The objective of Silverlight is like run desktop like application on the web or mobile browser. But this doen't mean that Silverlight is for web or mobile application developments. You can use Silverlight for desktop applications, but here I will more concentrate on how to develop rich interactive web or mobile applications using Silverlight.

Download Silverlight Click Here

Silverlight uses two components, where Silverlight runtime for web browser to run your Silverlight application on the web browser and Silverlight development environment plug-in for Microsoft Visual Studio. To browse or run Silverlight application you only need Silverlight runtime. If you developing web application using Silverlight technologies you need to install Silverligth plug-in for Visual Studio.

Silverlight Showcase

Silverlight Showcase is online collection of live sample applications developed using Silverlight. This is a good collection for beginner to understand what are the capabilities of Silverlight.

Let's moving to simple Silverlight project and understand the features of Silverlight. First you need to download Silverlight development plug-in for Visual Studio. Download Once you successfully installed Silverlight into your Visual Studio Development Environment, it will show you two more project types called Silverlight Script Web and WCF Service.

Fig 1: Silverlight projects

Here we select Silverlight Script Web project type, give project name and click ok button. Now you well have new Silverlight project opened. In the solution explorer you can see that few new pages have been created. Default.html and Silverlight.js are the most important pages. Default.html file is the default page when you run your Silverlight application. Silverlight.js is the code behind JavaScript file. You can run this application and see.

Fig 2: Silverlight project solution explorer

Once you debug your application if you get "Script Debugging Disabled" error message you need to go to your default web browser and enable Script Debugging feature.

Fig 3: Script Debugging Disabled Message

Once you run your project you will get simple web page with "Click Me" button. Once you click on the button you will get small pop-up message. You can see that this button is JavaScript button, not web control and it doesn't take page refresh.

Fig 4: Sample Silverlight Project

This is the empty sample project. But what we need to develop our own application. Let's see how we can achieve this. So far in your solution you have only Silverlight web project. Now we need to add Silverlight Application to your solution. Right click on the solution and select new project and add "Silverlight Application" project.

Fig 5: Add Silverlight Application Project

Now you have two projects in your solution. Also you can see that additional pages have been added to your previous Silverlight web project automatically. In my example SilverlightTest is the web project and SilverlightApplication is the application project. In previous in your web project had only Default.html page, but now you have SilverlightApplicationTestPage.html page as well. This page has reference from web project page to application project page. Now you can develop your application in SilverlightApplication project and refer them in web project to run on web browser.

Fig 6: SilverlightApplication Project in Solution Explorer

Now let's look at on SilverlightApplicatio project. There you can see MainPage.xaml file. This is the template file for your SilverlightApplicationTestPage.html file. Now you can add Silverlight controls to MainPage.xaml to build your first page. Now open MainPage.xaml page. In Toolbox window you can see that new collection of Silverlight XAML Controls.

Fig 7: Silverlight XAML Controls

Any control in the Toolbox you can drag and drop into your MainPage.xaml page and build your Silverlight page. Here difference than now ASP.NET web page development is, you have define the page template; Not actual page. I am going to add a button to your MainPage.xaml page and write some code for that button call. Open MainPage.xaml page and drag and drop "Button" control from Silverlight XAML Controls. Now you can see the XML tags for empty button. You have to define that button as you like. I have given a name, height, width, click event and content to display for this button. Name is "testButton", height: 100, width:200, button click event name is "Button_Click" and content display on the button is "This is test button". Also you can see that Grid control already been added automatically called "LayoutRoot".

Fig 8: Silverlight MainPage.XAML page source

Now our first Silverlight page done. Next step to write some code for this button call. Right click on the MainPage.xaml page and select "View Code" option and go to code behind.

Fig 9: Silverlight Button Event Handler Code

If will open new page called MainPage.xaml.cs file. If is more like normal ASP.NET page, but it is not. What I am going to do here is once click on the button, it will show the current time without refreshing web page. For that I will add another label for your MainPage.xaml as previous. Then go to Button_Click event and write our server code.

Fig 10: MainPage.xaml.cs File

private void Button_Click(object sender, RoutedEventArgs e)
{

this.myLabel.Content = System.DateTime.Now;

}

Now this is the important thing. You wrote server code or C# code for your web button. That button is call a JavaScript and that JavaScript call your server code. So that once you click on this button it goes to server to accomplish your task but it doesn't not refresh your page. Run this project at see how your button work.

Fig 11: Show Time Silverlight Application

Click several time on the button ans see current time changes, but it doesn't not refresh the page.

Important things to learn here is how simply you can build such rich interactive web application with Silverlight. Here is very simple example, you can try lot more complex project using Silverlight. Will meet again with some other projects. If you have any problem please post them on comment section and I will attend to them.

Read More:

CodeProject

Seadragon Enables Smooth Image Browsing

noreply@blogger.com (nandun) — Thu, 29 Jul 2010 04:11:00 +0000

Seadragon service enables web experience to browse graphics and images very smoothly regardless of the amount of data or the bandwidth and network traffic. Using Seadragon service you can make your photo album, photo sharing ...etc online without writing single line of code. First you need have your images host on the Internet and valid URLs for them. Then simply submit those image URLs to Seadragon.com site.

Here is the example work I did. Click here

You can see that the original image host in this blog site. I have given the URL of that image to Seadragon.com and create my album. If you load the original image and Seadragon album you can see that how smoothly you can browse images using Seadragon. Also if you need to embed the Seadragon album into your page you can generate embedded code for your created album.

You can also create a Seadragon experience using either Silverlight (with Deep Zoom) or JavaScript (with Seadragon Ajax). Either way, you'll want to know how to create Seadragon content.

AJAX Extensions on Microsoft Visual Studio 2008

noreply@blogger.com (nandun) — Fri, 23 Jul 2010 09:08:00 +0000

AJAX is a new trend in web development where it gives very smooth functionality for your website. In simple term we can use AJAX technology to refresh individual parts of the web page without refreshing whole page. This feature will increase the efficiency of your web page, smooth operation and enable more description web page design.

What is AJAX?

AJAX = Asynchronous JavaScript and XML.

AJAX is not a new programming language, but a new way to use existing standards.

AJAX is the art of exchanging data with a server, and update parts of a web page - without reloading the whole page.

Microsoft Visual Studio 2008 is coming with rich collection of AJAX controllers built in. AJAX is based on Java and JavaScript so it is nothing to do with .NET or Visual Studio. But most importantly we can easily use AJAX with most of the web development project. With AJAX Extensions of Visual Studio 2008 we can use AJAX with the visual studio development environment. This is really easy and fun. Let do it with a small project, so that you can easily understand the concept.

In this project I will show you how to develop a web page that will display current server time stamp without refreshing web page again and again. To get server time web page should send request, get response and display it. In this basic example I am using ScriptManager and UpdatePanel controllers. ScriptManager is a highlevel controller define with respect to the web page. But you can have one or more UpdatePanel for a given web page. Those UpdatePanel s can be individually update based on deferent events. So you should understand that we can perform several functions on the web page at a given time synchronously using multiple UpdatePanel s.

Fig 1: AJAX Extensions Toolbox

AJAX toolbox contains ScriptManager, ScriptManagerProxy, Timer, UpdatePanel and UpdateProgress controllers. More frequently we use ScriptManger and UpdatePanel. Update panel we use to place controllers that need to get update with the page events, but without page refresh. In this example you can see I have add ScriptManger and UpdatePanel. Within UpdatePanel there is ContentTemplete, inside that you can I have placed two buttons and one label. Once you click on one button it will display the current server time on the label and click on other button will execute javascript method "test".

Fig 2: How to use AJAX ScriptManger

Fig 3: How to use AJAX UpdatePanel

The final step is to write code for server side operations. Write respective server side code inside the particular controllers' (Eg: button, menu...) event handling methods same as you do in normally applications. But here different is this server side code will execute on server and send results to corresponding controller but no page refresh.

Fig 4: How to write server side coding in AJAX

Microsoft PowerPoint 2007 Training - Part II

noreply@blogger.com (nandun) — Tue, 16 Mar 2010 03:20:00 +0000

Use Advance Drawing Toolbar

Working with movies and sounds

Use Action Buttons

Hyperlink Tools For Linking Objects

Page Setup And Printing Slides

Use Powerpoint For Web Applications

Preparation Of Slide Show

Books:

Learning Microsoft Office 2007
Microsoft Office PowerPoint 2007 Step by Step (Step By Step (Microsoft))
Microsoft Office PowerPoint 2007: Complete Concepts and Techniques
Teach Yourself VISUALLY Microsoft Office PowerPoint 2007 (Teach Yourself VISUALLY (Tech))
Microsoft Office PowerPoint 2007: Comprehensive Concepts and Techniques (Shelly Cashman)

Downloads:

Microsoft Office Ultimate 2007 FULL VERSION [DVD]
Microsoft PowerPoint Home and Student 2007
Microsoft PowerPoint 2007 Computer Based Training DVD Rom - Learn MS Power Point with 8 Hours of Lessons on CD That Are Well Organized From Basic to Advanced Features. Over 110 Powerpoint Features Explained By an Experienced MS Office Instructor: Brush up on Your Computer Software Skills with CBT Slide Show Presentation Training
Microsoft PowerPoint 2007 Version Upgrade

Microsoft PowerPoint 2007 Training - Part I

noreply@blogger.com (nandun) — Mon, 08 Mar 2010 05:33:00 +0000

Microsoft PowerPoint 2007 Environment

Slide Design and Slide Layouts

Custom animation

Slide transition

Download:

Microsoft PowerPoint 2007
Microsoft Powerpoint Home and Student 2007
Microsoft PowerPoint 2007 Version Upgrade
Microsoft Office Ultimate 2007 FULL VERSION [DVD]
Microsoft Office Professional 2007 Video Training Courses - Excel, Word, PowerPoint, Outlook, Publisher and Access 2007 by Amazing eLearning

Books:

Microsoft Office PowerPoint 2007 Step by Step (Step By Step (Microsoft))
Microsoft Office PowerPoint 2007 Plain & Simple
Microsoft Office PowerPoint 2007: Complete Concepts and Techniques
Teach Yourself VISUALLY Microsoft Office PowerPoint 2007 (Teach Yourself VISUALLY (Tech))

Failed to open a rowset. Details: 42000:[IBM][iSeries Access ODBC Driver]Statement violates access rule: Connection is set to read only. Failed to open a rowset.

noreply@blogger.com (nandun) — Mon, 22 Feb 2010 05:54:00 +0000

Failed to open a rowset. Details: 42000:[IBM][iSeries Access ODBC Driver]Statement violates access rule: Connection is set to read only. Failed to open a rowset.

This is very common error when you try to deploy your Crystal Report reports in production environment. But most of the time people doesn't have proper solution. This error can be raised due to various reasons. But as I feel Crystal report gives very generic errors rather giving specic error message. So that most of the time we need to spend lot of time to figure out the exact issue. As of my experience this error gives when your crystal report unable to retrive data from your database properly. Here in this case iSeries Acess ODBC Driver has used. You might use some other driver to communicate with your database. But you will get very similar error with respect to your driver. Whether you are using stored procedure to retive data or directly access the database table; doesn't matter this error might occur.

First thing that you can try out is check whether you have configured "AllowProcCalls" registry entry. You can check this, go to start button, then run. In run dialog box type "regedit" and enter. In the RegEdit you need to locate HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI. Then find your ODBC data source that your crystal report retrive data from. Verify that there is an entry called "AllowProcCalls" with a value of "1". If AllowProcCalls entry doesn't exists you can create it by right click on your ODBC data source, then select New : String Value. Enter in AllowProcCalls and enter. If AllowProcCalls entry has value other than 1 you can change its value by double clicking on that entry or right click on the entry and select modify. Enter 1 and press "OK".

Fig 1. AllowProcCalls entry in RegEdit window

Then load your Crystal Report again and check whether your problem solved. If you are getting further errors please let me know so that I will look in to them separatly.

More references:

Crystal Reports 2008 For Dummies
Crystal Reports 2008: The Complete Reference (Osborne Complete Reference Series)
Crystal Reports XI: The Complete Reference (Osborne Complete Reference Series)
Upgrade Crystal Reports 2008 Win Nul
Crystal Reports 10 For Dummies

How To Generate MD5 Hash Code Using C#.NET

noreply@blogger.com (nandun) — Wed, 06 Jan 2010 05:58:00 +0000

MD5 Hash code is a unique string of characters that can be generated for a given character string. This Hash code is very important when you compare string values. It is not technically correct to compare two string directly. Good method is generate Hash code for both the strings and compare those Hash codes. Virtually it is agreed that accuracy of Hash code comparison is much higher. Not only to compare two strings, we can use Hash code to compare two files as well. There it is required to read a file as byte stream and generate Hash code for that stream. To compare that stream with second file you need generate Hash code for second file as well using same method and compare those Hash codes. Using this method you can check whether any changes has happened to the content of the file as well as meta data of the file. So that MD5 Hash code is really important in various scenarios. Most of the programming languages are directly support for MD5 generation. Even SQL commands are available to generate Hash code directly at database level. Here I am explaining one of the methods that can be easily used.

First step is to generate MD5 Hash for any object is convert that object into a byte array. For this we take MemoryStream and BinaryFormatter objects.

MemoryStream fs = new MemoryStream();

BinaryFormatter formatter = new BinaryFormatter();

Serialize() method is used to directly convert object into MemoryStream. Before this operation to be thread-safe we should lock the object.

private static readonly Object locker = new Object();

lock (locker)

{

formatter.Serialize(fs, objectToSerialize);

}

return fs.ToArray();

Now we are ready to generate a MD5 Hash code for above serialized byte array. MD5CryptoServiceProvider is used to compute Hash for given stream of bytes. Finaly convert the each byte to Hex and appending it to the StringBuilder to build final string.

MD5 md5 = new MD5CryptoServiceProvider();

try

{

byte[] result = md5.ComputeHash(objectAsBytes);

StringBuilder sb = new StringBuilder();

for (int i = 0; i < result.Lenght; i++)

{

sb.Append(result[i].ToString("X2"));

}

return sb.ToString();

}

catch (ArgumentNullException ex)

{

// Exception Message

}

You need to include followings

using System.Security.Cryptography;

using System.Runtime.Serialization.Formatters.Binary;

using System.Runtime.Serialization;

using System.Reflection;

using System.Threading;

Now you done! This method can be used for any string or any file to compute MD5 Hash code. If you need any further clarification please list them under comments section. You can find more details here:
Illustrated C# 2008 (Windows.Net), Pro C# 2008 and the .NET 3.5 Platform, Fourth Edition (Windows.Net), C# 3.0 Design Patterns, Head First C#

Structure of Drive System

noreply@blogger.com (nandun) — Tue, 05 Jan 2010 15:12:00 +0000

Figure 1: Structure of drive system

Load is the most important component. All other units are arranged to serve the requirement of the load. Any design begins with a list of specifications for the load. This depends on the type of the load and its environment. We need to answer several questions before preparing specifications.

Eg:

Whether one, two or four quadrant operation is necessary
Whether servo or adjustable speed action is necessary
Whether breaking energy is to be dissipated or returned back to the utility
Whether a soft or hard start is suitable
What are the range of speed and the resolution of the speed control?
What are maximum torque?
Is there a space restriction?
Is there a noise level restriction?
Is there some starting current restriction?
Is there any EMI (Electro Magnetic Interference) restriction?
Is there supply end restrictions? (Eg: Total Harmonic Distrotion)?
Whether the energy efficiency is a prime consideration

and many more.

The components in the drive system are independent. The load to some extent can suggest the type of motor required. The motor selection it self is a challenging task that requires good understanding and skill about the performance of different motors. This difficulty arise due to the availability of a large count of competitive motor types. The power electronic converters is often specified by the motor selected. For DC motors we need one type of converter but for AC motors we need a different type converter. A stepper motor needs a totally different converter and so on.

Eg:

Figure 2: Table of Choices of power electronic converter

Additional stages may also be necessary on top of the basic converter circuit to accommodate such features as returning breaking energy back to the supply network etc. In all the power converters listed in the table DC was used as input source. This is not because the primary power available from the power system is DC but the common practice of a diode rectifiers unit to interface the power system (This is done to minimize the distortions at the supply end).

Figure 3: AC to DC Converter

Microelectronic control unit is central to all other components in the system and it co-ordinates the activities of all. It receives feedback from the load and motor and dictates terms to the power electronic converter according to the user input. The microelectronic control unit is a computer. It can be a micro-controller or is some cases a PLC. Discretely assembled microelectronic control units too are not common.

Overview of Technology State

noreply@blogger.com (nandun) — Tue, 05 Jan 2010 14:37:00 +0000

Role of power electronics and drivers

Power controlling using electronics consider here
Signal controlling is consider about controlling information

Power electronics is about control of power electronically. Range of power can extend from some fraction of watt to several mega watts (MW). Drives are about the control of mechanical motion. It can be a linear motion, rotary motion or their combination. There is a greater compatibility between power electronics and drives as the former can provide smart control of power for the drives. This is evident from the varieties of fascinating motion control systems we find today.

There are several terms used in the context f motion control.

Motion control systems
Mechatronic systems
Drive systems
Adjustable speed drive systems
Servo drive systems

Motion control system is the name used in west (Europe) to represent the low power drives (Computer pheripherals, home appliances...etc) upto several KW. Mechatronics system is the name used in the east (Japan) for the same, that is the low power drives. Drive system is the name that represent drives of the entire sprectum of power. Adjustable speed control system is the name reserved for the sub category whose steady-state performance only is emphasize. Servo drives in the name reserved for another sub category whose both the transient and the steady-state performance are empasized.

Automation is a multidisiplinary technology that integrates the knowledge of diverse areas such as instrumentation, remote sensing, advance control, data processing, computer technology, microelectronics, mechanics process system, motion control and many more. Motion control is one of the thrust areas that propells automation industry hard.

How To Insert Single Quote Into DB2

noreply@blogger.com (nandun) — Mon, 29 Jun 2009 10:04:00 +0000

If you try to insert single quote into DB2 sql table directly, it will give an error message due to single quote is reserved for mark a string value in sql. It is not allowed to use escape sequence for single quote with sql. Below example is incorrect with sql syntax.

INSERT INTO CUSTOMERS ( COMPANY_NAME ) VALUES ('Nandun\'s Company')

Here middle single quote is not valid even it has used the escape sequence. The easiest method to insert single quote into sql table is replace single quote with double quote.

INSERT INTO CUSTOMERS ( COMPANY_NAME ) VALUES ('Nandun\"s Company')

In second example I have replaced the single quote with double quote, but once you execute this command it will insert single quote instead of double quote.

You can use following code in C#.NET to replace single quote with double quote.

Replace("\'", "\"")

If you have any question you can list them under comments section.

Crystal Report Toolbar Images Not Displayed In ASP.NET

noreply@blogger.com (nandun) — Mon, 08 Jun 2009 07:49:00 +0000

If you have used Crystal Report (Crystal Reports 2008 Official Guide) with Microsoft ASP.NET, you might have face this issue many times. This is a common problem with Crystal Report deployment and many people don't have proper solution for the problem. Crystal Report Toolbar images not shown in deployed environment is one of the main inconvenient with the tool that is leaded many developers not to use Crystal Report tool as their reporting tool even though Microsoft Visual Studio distribute Business Objects Crystal Report Tools free of charge. Even though your report is perfectly working inside the report viewer, it is not useful if the report viewers toolbar is not working properly. You can not navigate through multiple pages, can not export your report, can not print the report...etc. So that it is equally important to work your report and report viewer both correctly to feel end user happy reporting experience.

I have found few ways to overcome this issue and first solution is install Crystal Report Components for .NET using your Visual Studio Installation CD/DVD set. This method is applicable most of the time Vista operating system and XP with newly patches. I have experienced even though the the installation goes well, still problem might persist due to some problems of locating the installed images. Here you need understand that if the installation went well the required images will copy into your hard drive, but some cases the report viewer is unable to locate them. If the problem is still persist you can go into next solution where install "crredist2005_x86.msi" from SAP website or Upgrade Crystal Reports 2008 Win Nul. Business Object's Crystal Report Viewer is distributed by SAP and they have provide installation for Crystal Report Views as well. In same way you can install this msi file and check whether your problem is solved. This will install "Crystal Reports for .NET Framework 2.0 (x86)" into the system and it is having all the necessary components to run your report in crystal report viewer.

Above two methods are not very specific and blindly hit the target. But try them first and most of the time you will get happy results. But still if you are getting same error you have another method. After install above components and still you have error means all necessary components have been installed properly but your report viewer is unable to locate the images. Then easies them is locate your image file location and register with your report viewer. How you can do this? This depends on the way you have programmed your report. You have basically two methods to program either you can define all the parameters when your create your report viewer.

Fig 1: CR:CrystalReportViewer code section
or if you drag and drop the report viewer control from toolbox of visual studio editor it will insert the report viewer component separately and it takes all the configuration details by including "default.css" style sheet from "C:\inetpub\wwwroot\aspnet_client\system_web\2_0_50727\CrystalReportWebFormViewer3\css\default.css" in header section of the page.

Fig 2: "aspnet_client" location include from page header section

In both methods is has been loaded files from the same location. aspnet_client folder is normally locate under "C:\inetpub\wwwroot\aspnet_client" if you use default configurations while you installing IIS server. Now you know the place where your toolbar image files are located, but why the system is unable to locate them? Due to various reasons this might be happened. Whatever the reason if we could tell the IIS server where these image files are located, your problem is solved and report will work fine. So the easiest method to define files in any location IIS server manager is to create a virtual directory. If you analyze the above two code sections you will notice that all the path have been defined with respect to "aspnet_client" folder. So that you need to create virtual directory under your web site which will locate the "aspnet_client" folder.

Fig 3: Add Virtual Directory To Web Site

Virtual directory alias should be "aspnet_client" and browse the "aspnet_client" folder from physical path field. Reset you IIS server and browse your web site and see how your report viewer is loading your report without any error.

Still you are facing any issues, please feel free to mention them under comment section so that we can find solution for them as well.
Good Luck !
Find more details Crystal Reports 2008: The Complete Reference (Osborne Complete Reference Series)

Save Millions Of Dollars, Don't Pay For Graphic Tools

noreply@blogger.com (nandun) — Fri, 29 May 2009 04:24:00 +0000

Are you a graphic designer, web designer or digital artists who is paying back most of your income for software tools that you are using for your creations? What will be your net income if you could save money that you are paying for those software tools? Yes, there are tons of free tools that you can use as alternative graphic software tool. Some of the free tools having rich set of functions than commercial tools, but most of the people are having lack of knowledge about them and their features. So, I decided to introduce few of them that I am using for my creations without paying any dollar for any company. That means cost for my creations are negligible and income is really high.

Tools that you need to do any kind of graphical creation such as photo editing, painting, animation, image processing, video processing etc can be found in free and open source world. Some people think that free tool are not well developed, not very user friendly, no help or support etc, but according to my experience this is not 100% accurate. Sometime you might face some difficulties, but millions of people are to help and guide you since they don't expect any return from you. I am also doing same thing here and if you have any question you can post under comments section and I will attend to it to help you. So try and feel the different of free software and how you can save you income.

Today I am going to introduce a nice photo editing graphical tool that can be easily used to replace software like Adobe Photoshop. Adobe Photoshop is rich photo editing tool that most of the artists are using around the world but the fact is high cost. GIMP is a free tool that you can be used similar as photoshop but 100% free of charge. GIMP stands for GNU Image Manipulation Program. This tool is also widely used around world for photo editing and graphic designing purposes.

You can be download GIMP from here.

GIMP is available for Microsoft Windows and Linux platforms. The user interface of the tool has been designed in a way that new users can easily start work with and experienced photoshop users are also will quickly dive into it.

Fig 1: Loading GIMP 2.6
GIMP user interface has few major sections; drawing area, toolbox, layers window, channels window, history window, navigation area, paint brushes and settings section. Drawing area is used to design your creation, toolbox is having all required tools, navigation section can be used to navigate on entire creation if the image is larger than the drawing window. Other sections are mainly used as supporting windows for rich functionalities of the tool.
Fig 2: GIMP User Interface

Try all the tools in the toolbox and get familiar with the tools and their functionalities to become GIMP guru. It is very important to be very familiar with tools and filters of the tool. You can change the default settings of any tool or filter to perform millions of functionalities using this tool.
Fig 3: GIMP Toolbox

Filters are the next section that you need consider more. By looking at the filters list you might not get proper understanding of the importance of them. But once you familiar with them filters are really critical to finish the quality work. GIMP is having very rich set of filters by changing their default configuration you will have millions of effects.

Fig 4: GIMP Filters

It is really important to familliar with these filters to take maximum usage of them.

If you have any further questions you may post them under comments section.

No More Database Programming Needed !

noreply@blogger.com (nandun) — Mon, 25 May 2009 02:57:00 +0000

Are you tired in writing complex code for your database design? Want to be little relax? This article will help you to enjoy your job.

In early days we had to write coding from the scratch to implement our database designs. Later people moved to database designing graphical tools. The latest trend of designing databases is use database navigation maps where you can visually feel your database design. This method is very useful if your database is little complex and you have lot of key constraints, referential integrity constraints, indexes and triggers etc. Using database navigation maps you can see either the entire database or part of it, how the tables are integrate each other, what are the keys you have defined for tables and references etc. Most importantly you don't need to write any single code or no need to remember complex SQL syntax.

Database Navigator Maps in IBM iSeries Navigator is providing very easy and flexible way of designing you database. Sometimes you might use this tool as visual tool but here I am explaining how you can use this tool as development tool to implement your database physically. Login to iSeries Navigator and browse databases section. If you are not familiar with the iSeries Navigator read this article. Under database section you can see Database Navigation Maps in tree view.

Fig 1: Select Database Navigator Maps
Once you select database navigation maps you will see existing maps in right hand side pane. Double clicking on the map you can open it and see. But let see how you can design new database using this tool. Right click on Database Navigation Maps and browse New -> Map.
Fig 2: Create New Database Navigation Map

This will open Database Navigator window which allow you to design your entire database. There it will list all the existing schemas and you can design your database under any schema listed there.
Fig 3: Database Navigator Window

Drawing area is the place you can use to draw or design your database. Right click on the drawing area and brows Create and select which you want to create. You have options to create database table, view, index, journal, alias, materialized query table and user defined relationship. By default user defined relationship is disabled and later will discuss how to write user defined relationship with the navigator.

Fig 4: Create Objects in Database Design
Once you create new element it is again open same window as iSeries Navigator opens to create new elements. I have already discussed to work them and design your database. You read more details from this article.
Once you designed you database using this tool it will look like this.

Fig 5: Sample Database Navigator Map
Final step is save the successfully design database into you DB2 database management system. Select save option from the file menu then give a name for your map select schema in which you need to save the database.
Later if you want you can change this design any time and save it. Please note that if you save the Database Navigator Map that mean your are physically change your database.
While your friend is spending days to develop a database, you can simple develop your database withing few minutes and have a relax. So try and see how you can simplify your work and have a fun.
If you have any questions you can post them under comments. I will reply them.

How To Validate XML Document With ASP.NET

noreply@blogger.com (nandun) — Fri, 22 May 2009 02:27:00 +0000

In my previous article, we discussed on how to generate XML document or XML stream from your dataset. There I mentioned that one of the major advantage of converting a dataset into XML is we can easily validate our XML data against the XML schema. The XML schema is used to define the format, data types and key constraints that you want to validate. The XML document or XML stream can be validate against the predefined XML schema and exactly you can get the validation error and on which tag that error is occurred.

First you need to have a XML document to validate. There are several ways to convert your data into XML documents. In previous article I showed you one such method. In this article I will show you how to do a validation with XML schema for existing XML document.

Step 1:

Define you XML schema that you need to validate your data with it. In Microsoft Visual Studio 2005 it very easy to define your XML schema since they have provided a graphical tool. First add XML schema file to your project solution. Please note that both XML Schema and Dataset file extensions ".xsd" since they have used common technologies. But here you should only add XML schema file not Dataset file.

Fig 1: Add XML Schema File to Solution
Using XML Schema Toolbox you can define element, attribute, attributeGroup, complexType, simpleType, group, facet, key and relationship in you schema.
Fig 2: XML Schema Toolbox
Fig 3: Sample XML Schema
Once you draw your XML schema here it will automatically generate XML code for the schema.
Step 2:
Next step is to load your XML file and validate it against the schema defined above. You need to load both XML document and XML schema into memory stream. Add resolver to pass security if accessing web site to receive schema. Last step is validation of XML document. You need use to following namespace in you coding.
using System.IO;
using System.Xml;
using System.Xml.Schema;
FileStream is used load XML file and define XmlDocument called "xdoc". XmlReaderSettings object is used to set XML Schema, XMLResolver and ValidationType. Load() method is used to load XML document and Validate() method is used to validate the XML document.
//load instance into memory
FileStream fs = File.Open("../../XMLFile1.xml", FileMode.Open);
XmlDocument xdoc = new XmlDocument();
XmlReaderSettings settings = new XmlReaderSettings();
settings.Schemas.Add(null, "../../XMLSchema1.xsd");

//add resolver to pass security if accessing web site to receive schema
XmlUrlResolver resolver = new XmlUrlResolver();
resolver.Credentials = System.Net.CredentialCache.DefaultCredentials;
settings.XmlResolver = resolver;
//this line is necessary for validation to work
settings.ValidationType = ValidationType.Schema;
ValidationEventHandler veh = new ValidationEventHandler(xvr_ValidationEventHandler);
settings.ValidationEventHandler += veh;
XmlReader reader = XmlReader.Create(fs, settings);
xdoc.Load(reader);
xdoc.Validate(veh);
ValidateEventHandler is used to define what action to take if the XML document is invalid. In this example I have written separate method called "xvr_ValidationEventHandler" to fire when the xml schema is not valid. Inside this method you write what actually you want to do if XML file is not valid according to the XML schema.
private void xvr_ValidationEventHandler(object sender, ValidationEventArgs args)
{
// The xml does not match the schema.
this.richTextBox1.Text = args.Exception.InnerException.ToString();
}
In this example I have written the Exception message into rich text box once the XML document is invalid.

Try and see how easy to work with XML language.

Working With Dataset And XML In ASP.NET 2.0

noreply@blogger.com (nandun) — Thu, 21 May 2009 03:01:00 +0000

XML data definition format is heavily used in nowadays applications since it is very rich data definition method. Working with XML data is very customizable, easy and reliable. Important features of XML language are;

well defined schema
purely character based data definition method
customizable tags
easy validation of XML documents

In ASP.NET it provides lot of shortcut methods to work with XML data. Actually .NET Frameworks most of the components fully based on XML languages. Few examples are Data Grid, Data Set and Class Designer etc. Due to this reason you can easily convert data in dataset to XML document and read data from XML document to feed into dataset. Why it is important to convert dataset into XML documents is a good question to analyze. There are few reasons to explain here, first thing is dataset is a kind of a special data format and not exchangeable with different applications. Transfer through web protocols is not straight forward with dataset, but XML data is based on characters and easily pass through the network. Most importantly validation of data is very easier with XML data that data in dataset. There are buit in validation functions with XML documents in ASP.NET.

Generate XML file from dataset

// Connect to database
OleDbConnection con = new OleDbConnection('');

// Create new dataset
DataSet ds = new DataSet();
// Create new data adapter
OleDbDataAdapter da = new OleDbDataAdapter();

// Create SQL command
OleDbCommand cmd = new OleDbCommand("SELECT * FROM tblMyData", con);

// Set SQL command to data adapter
da.SelectCommand = cmd;
// Fill dataset
da.Fill(ds);

// Write data from dataset to XML file called "YourXMLFile.xml"
ds.WriteXml("c://YourXMLFile.xml");

Read data from XML file and fill dataset

"WriteXML()" method is used to write XML data from dataset into physical file, memory stream or character stream. In same way you can use "ReadXML()" method to read data from XML file and assigned to dataset.

How To Specify Unique Key/Primary Key Constraints In DB2

noreply@blogger.com (nandun) — Mon, 18 May 2009 02:39:00 +0000

Using iSeries Navigator you can very easily specify Unique Key and Primary Key for database table in DB2 database. Most of the people are not well aware that DB2 is relational database and it support all the relational database concepts. I have experience that most of the developers are not using key constraints, referential integrity, triggers etc. But most importantly DB2 is support for all these features. Let's look at one by one how these concepts can be implemented using iSeries Navigator on DB2 database.

To create Unique Key or Primary Key for a given table you need to go the table definition. Right click on the table that you want to modify and add new key and select "Definition" option.

Fig 1: Table Definition Option

In table definition window go to "Key Constraints" tab and click on Add button.

Fig 2: New Key Constraint Window
In New Key Constraints window specify constraint name or leave "Constraint Name" field as it is to system generated constraint name. Then select whether you want to specify unique key or primary for the table. In "Available Columns" box you will see all available columns in the table and you can select either one of them or more than one columns for composite key. Once you select column click on Add button at middle of the window to put them into "Selected Columns" box. You can change the order of columns if you have selected more than one column, by using Move Up or Move Down buttons. If everything completed click on OK button to add this constraints to the table. You can add more that one constraint for a given table as you wish. Also note that if the table is having conflicting data to create new key constraint, you might face issues while you creating these constraints. Then find the conflicting data set and correct them possible or remove them from table so that you are able to create new constraint successfully.

Crystal Reports in Microsoft Visual Studio 2005

noreply@blogger.com (nandun) — Fri, 15 May 2009 02:55:00 +0000

With Microsoft Visual Studio 2005 you can develop applications with Crystal Reports without using separate Crystal Report application installed in the development machine. They have provided Crystal Reports tool in standard toolbox in Visual Studio 2005 environment. Simply you need to drag and drop these controllers and develop your reports same as previously with Crystal Report. Advantage is you don't need to buy separate Crystal Report application and install them in development and deployment environments.

Fig 1: Crystal Reports Tools in Microsoft Visual Studio 2005

If you have worked with Crystal Report previously, you might have experienced that working with Crystal Report is not very straight forward. Most of the time when you try to deploy developed reports most beginners face problems such as dll component registry problems, crystal image handler problems etc. With this method once you installed complete .NET framework in you deployment environment most of these problems can be easily overcome.

How To Create Stored Procedures Using iSeries Navigator

noreply@blogger.com (nandun) — Thu, 14 May 2009 03:13:00 +0000

In conventional method it is not very straight forward to write stored procedures with DB2 in AS400 environment. You might need to remember lot of syntax or might need to refer books to find syntax to code the procedures. This is very inefficient method for today's database programming context. iSeries Navigator has been provided very cool feature to develop your stored procedures from the iSeries Navigator graphical UI. You don't need to remember all the syntax to write database coding and the tool itself given you all the syntax which are required to write your coding. Only you have to do is insert them into your coding and make necessary modifications.

Login to your iSeries Navigator and browse your database that you want to create new stored procedure and select "Procedures" section.

Fig 1: Select you database and Procedures in iSeries Navigator pane
Right click on Procedures and select "New" to create new stored procedure. There are two options to select either "SQL" or "External" type procedure to create. If you select ""SQL" you can write your new procedure using SQL syntax. Also you can use separate external program written using C, C++, CL, COBOL, COBOLLE, PLI, REXX, RPG, RPGLE and Java by selecting "External" option. This is very flexible method since high level programming languages are provided much more freedom to code complex coding than SQL language. This article is focus on develop a procedure using SQL language.

Fig 2: Create new SQL type procedure
Provide procedure name, description, maximum number of result set, data access and specific name in General tab of "New SQL Procedure" window.
Fig 3: New SQL Procedure General Tab

In Parameters tab you can specify what are parameters for the procedure. Click on "Insert" button to add new parameter, once you added new parameter you can change its name, data type, length and In/Out option.
Fig 4: New SQL Procedure Parameters Tab

Next step is develop SQL logic for the procedure. For that select "SQL Statements" tab in New SQL Procedure window. In SQL Statements tab you will have "SQL Statements examples" drop down list, Insert button and Statements section. From drop down list select what is the syntax that you want to insert into your code. This drow down list will show all the required SQL syntax to develop your SQL code. Once you select the statement, click on Insert button to enter selected statement into your code. After inserting default statement you can modify as you wish. For example you can change variable names, data types etc. Advantage here is you don't need familiar with all the syntax, but you can simply insert them and modify according to your requirement. You can put any number of statements to build up your SQL code.
Fig 5: New SQL Procedure SQL Statements Tab
In the above example I have inserted variable initialization and alter table SQL code. You can modify this inserted default code like below example.
SET myCounter= 4;
ALTER TABLE Customer ADD COLUMN Age INTEGER;
In first line I have initialized the variable called "myCounter" to 4. In second line I have alter the Customer table and add Age column.
In this way very easily you can develop your SQL program for your stored procedure. This is very efficient method and very time saving. But initially you might need to get little familiar with tool. Good luck and happy coding !

How To Send An E-Mail Using ASP.NET

noreply@blogger.com (nandun) — Wed, 13 May 2009 02:39:00 +0000

Sending an E-mail from your web site is really simple with ASP.NET. First of all will look at what actually happened when an E-mail is sending from a web site. First step is preparing your complete E-mail programmatically. For that you need to set source e-mail address, destination e-mail address, e-mail subject, e-mail body, SMTP (Simple Mail Transfer Protocol) mail server and SMTP port of your server. Once you prepare your E-mail in correct format, there is only one step to send the E-mail to your destination addresses. For that you need to pass the E-mail request to message queue of the SMTP server through SMTP port. By default port 25 is used as mailing port. That is only what you have to do and rest of the relaying of E-mail part will handle by the SMTP server itself. SMTP server is responsible to pass your E-mail to respective destinations.

System.Net.Mail namespace should import using following code.

using System.Net.Mail;

Code for prepare your E-mail format is as follows.

// System.Web.Mail.SmtpMail.SmtpServer is obsolete in 2.0
// System.Net.Mail.SmtpClient is the alternate class for this in 2.0
SmtpClient smtpClient = new SmtpClient();
MailMessage message = new MailMessage();

MailAddress fromAddress = new MailAddress(fromAdd, displayName);

// You can specify the host name or ipaddress of your server
// Default in IIS will be localhost
smtpClient.Host = "smtpsvr";

//Default port will be 25
smtpClient.Port = 25;

//From address will be given as a MailAddress Object
message.From = "fromadd@yourdomain.com";

// To address collection of MailAddress
message.To.Add("toadd@yourdomain.com";);

message.Subject = "Your E-mail subject";

// CC and BCC optional
// MailAddressCollection class is used to send the email to various users
// You can specify Address as new MailAddress("admin1@yoursite.com")
//message.CC.Add("ccadd1@yourdomain.com");
//message.CC.Add("ccadd2@yourdomain.com");

// You can specify Address directly as string
//message.Bcc.Add(new MailAddress("bccadd1@yourdomain.com"));
//message.Bcc.Add(new MailAddress("bccadd1@yourdomain.com"));

//Body can be Html or text format
//Specify true if it is html message
message.IsBodyHtml = false;

// Message body content
message.Body = "Your E-mail message contents";

// Send SMTP mail
smtpClient.Send(message);

How To Set Session Timeout in Web.config

noreply@blogger.com (nandun) — Tue, 12 May 2009 02:53:00 +0000

Session timeout period can be set as you required simply changing web.config file of your web site. In ASP.NET web site once you add web.config file you can find tag. Inside this tag you can specify session timeout value. Add following code to your web.config file.

<system.web>
<sessionstate timeout="60"/>
</system.web>

In this example you have set sessionState timeout value to 60 minutes. You can change this value as you wish, but need to make sure that it is really required. For example if you set a very large value for timeout, your session will hang on forever in the server. This will lead some security issues, memory overflow issues and sometime unexpected behaviour of your web site. And also this value should not be very small values. For example if you have functions like uploading files in the web site, then you should give enough time to upload a file based on the size of the file, network traffic and bandwidth limitation of the client machine.

New Blog Site for Power Electronics and Robotics

noreply@blogger.com (nandun) — Mon, 11 May 2009 04:14:00 +0000

I lanched a new blog site for discuss about power electronics and robotics related topics. This site is intended to publish deep theoritical articles and practically implementations of power electronics and robot world.

http://www.elecsl.blogspot.com/

Identity Columns in DB2 AS/400

noreply@blogger.com (nandun) — Mon, 11 May 2009 02:49:00 +0000

Does DB2 support for identity columns? Yes, it is. All numeric data types in DB2 database support for identify columns. Identity columns means, a field or column in a database table which automatically set its values for a new row insert. You don't need to provide value for the identity field when you insert new row into your table. For example if you want to set your customer identification number grow like 1000,1001,1002,1003... , you can set customer identification number column as identity column and starting number 1000 and increment value is 1. Then when you insert next customer it will increase the maximum customer identification number by 1 and automatically insert into the table.

You can find iSeries Navigator from "Start -> IBM iSeries Access for Windows -> iSeries Navigator". Open iSeries Navigator and select your database and table that you need insert identity column. Keep in mind that you can only set identity only for numeric fields. You can either create new table with identity columns or set identity property for existing table.

Fig 1: Insert New Column with Identity

In Table go to Column tab and click on Add button to add new column. Specify column name, short name, data type text...etc. If you select numeric data type for you column you will see a check box "Set as identity column". Tick that check box to enable identity for this column. Once you check the check box it will expand the window which allow you to configure the identity settings.
Fig 2: Set as Identity Column

Set Increment to an any value that you want increment your identity value. If you set 1 here it will increase the existing maximum number by 1. Starting value is used to set increase first row. Minimum value and Maximum value are used to restrict the values to a particular range. Values to cache is used to load last maximum values to memory so that increase the maximum value by Increment value is not needed a database hit for read maximum value for the identity column. "Cycle values when the maximum or minimum value is reached" check box is used to set whether the repetative value range is necessary when the datatype is reached its maximum or minimum values. This option is not allowed if you have set the column as primary or unique key for the table. "Generate the values in the order requested" check box is used to set whether you need to set values for the column in order or not. For example if you delete any value in between the value range whether that value is reusable or not.
Once you set any column as identity you don't need to give values when you insert a record into table. This column will automatically will be filled by the DBMS itself.

Manage SQL Tables in IBM iSeries Navigator

noreply@blogger.com (nandun) — Thu, 07 May 2009 02:43:00 +0000

IBM iSeries Navigator is a rich client tool to work with DB2 database in AS400 machines. From your Microsoft Windows client machines through iSeries Navigator you can connect to remotely located DB2 database and work with it as simple as work in Microsoft Access database. You don't need work with console or do lot of coding which always lead to errors. Using iSeries Navigator you can very quickly develop you database and manage it very effectively.

Login

First step is to login to AS400 machine through iSeries Navigator. You need to provide server name, user id and password.

Fig 1: Login iSeries Navigator

Once you successfully login to the system in "Environment" pane it will list down all the entities that you can manage through iSeries Navigator UI. This list will vary based on the access permission to the connected AS400 server. In this article will discuss on how to work with SQL tables through the Navigator. At the end of the article you will realize how you can save your time by using iSeries Navigator for database management rather working on console window.

Work with SQL tables in DB2 database through navigator you need to select "Databases" section. Under Databases section you will have Schemas, Database Navigator Maps, SQL Performance Monitors, SQL Plan Cache Snapshots and Transactions.

Fig 2: Databases in iSeries Navigator

Under schemas section it will list down all the database schemas or different databases in the server. Database Navigator Maps is a graphical tool to visualize the database design. It is shown database tables, constraints and relationships or references in graphical notations. Database Navigator Maps can be used to manage your database as well. SQL Performance Monitors can be used to monitor and fine tune the database design. Transactions section shows Database Transactions and Global Transactions.

Select Schemas to Display

Expand the Schemas section to see the database you have already in the server. If it not listed your particular database you can add that database to navigator by using "Select Schemas to Display" option. Right click on the Schemas and select "Select Schemas to Display".

Fig 3: Select Schemas to Display

Enter the schema name or search for a schema that you want to show in the navigator using "Select Schemas toDisplay" window. Add the schema to "Selected Schemas" list and click Ok.

Fig 4: Select Schemas to Display Window

Create New Schema
If you want to create a new database or schema, right click on Schemas and select "New -> Schema". Specify a name for the new schema, whether it needs to add to displayed list of schemas and create as standard library. "Create in" is the system pool that you want to create your database in. "Text" is to discribe shortly your database for operator's purpose.

Fig 5: New Schema Window

Create New Table
Once your database schema is listed under Schemas section, select the database that you want to work with. It will display all objects belong to the selected database such as aliases, constraints, distinct types, functions, indexes, journal receivers, journals, procedures, sequences, SQL packages, tables and views. Select "Tables" from the tree view and right hand side pane will display all the tables in the database. Right click on Tables and select "New -> Table" to create new table in the database.
Fig 6: Create New Table Window

In New Table window specify the table name, schema and system table name and text. System table name is used to identify the table in the system. Text is to describe the table purpose. Use "Volatile Data" check box if the table need to be volatile.
Add Column to Table
Fig 7: Create New Column Window
Specify Column name, Short name for system purposes, Data type, Text and Heading for new column. Data type drop down list shows all the data types that you can use for your purpose. Click "Add" once you enter all the details to add the column into table.

IBM iSeries Navigator

noreply@blogger.com (nandun) — Wed, 06 May 2009 02:45:00 +0000

DB2 is one of the most popular Database Management System developed by IBM. DB2 is heavily used in various high end applications around the world on mainly AS400 platform. High security, higher performance, easy maintenance and backup/recovery procedure of DB2 are key factors to lead the industry. Even though DB2 is very powerful database management system, it was not very user friendly at early stages. Basically console based programming was required. Most of the users came from Microsoft Windows operating system background don't like to work on console and write everything manually. They always expect some graphical tool to make easy their work. IBM iSeries Navigator full fill this gap effectively and nowadays iSeries Navigator is heavily used desing and program database. Work with iSeries navigator is realy simple as work with Microsoft SQL server UI. iSeries Navigator is client tool that is allowed to work with your DB2 database remotely from your PC. Installing iSeries Navigator is really simple on Microsoft Windows operating system.

You can find iSeries Navigator from "Start -> IBM iSeries Access for Windows -> iSeries Navigator".

Fig 1: Open iSeries Navigator

iSeries Navigator is stand alone windows application which will facilitate almost all the services that can perform in DB2. This is very rich tool but most of the people are still not used effectively.

Fig 2: iSeries Navigator UI

iSeries Navigator main UI containts four major sections and a menu bar. Menu bar is not a complex one and any person can easily work with. Top left hand corner section called "Environment" section and it list down all the entities and services that you can use based on your permission level. Top right hand corner section shows the details for the selected entity of the environment section. "My Tasks" section list down all the possible tasks that can perform at DB2 server level. This list is not unique for all users and will vary based on the permission level that user have. "Environment Tasks" section list down all the task that can perform for the selected environment in environment section.

Common functions listing that can perform using iSeries Navigator is as follows:

Design and Create Databases
Create Database Schemes
Create Tables, Views, Stored Procedures, Functions, Indexes, Triggers and Journals
Create Users, User Groups and manage them
Manage Security
Basic Operations such as Messages, Printer Output, Printers and Jobs
Work Management - Manage Jobs, Queues, Subsystems and Memory Pools
Network Configuration
File System
Backup Policies
Application Developments

Will discuss one by one further in future articles.

Import/Export SSL Security Certificates in IIS

noreply@blogger.com (nandun) — Tue, 05 May 2009 04:54:00 +0000

We discussed how to enable SSL in a web site and create your own self-signed security certificate. Also you can use exsisting security certificates for a same server and same domain. You can use "Import" and "Export" facilities in Actions pane of Server Certificates window.

Open IIS Manager browsing Start -> Control Panel -> Administrative Tools -> Internet Information Services (IIS) Manager or run "inetmgr" command. Click on "Server Certificates" icon in middle pane of IIS manager.

Click on "Server Certificates" icon.

Fig 1: Server Certificates Icon

Select your existing certificate from Server Certificates window. Once you select your certificate it will show few new links in Actions pane to Export the certificate.

Fig 2: View, Export or Remove links

View link is for view details of the selected certificate, Export link for export the selected certificate and if you no more required selected certificate you can click on Remove link to remove certificate from the server.

Fig 3: Export Certificate Window

Browse the location that you want to save your certificate at "Export to:" and provide a password for this file to secure the certificate containts from unauthorized users. You need to provide same password when you import the certificate back.

Click on "Import" link and browse your certificate file to import.

Fig 4: Server Certificate Window

Fig 5: Import Certificate Window