The world is amazing

Ruby: Get input from console

2012-05-09T14:02:00.002-07:00

You can use the STDIN to get the input from console(shell/cmd/commandline).

to get a single character from the user.
chr = STDIN.getc

This is useful to implement something like "Press Enter to exit program." kind of things.

you can use gets, readline, etc with the STDIN.

FYI: for writing output to the screen, you need to use STDOUT.

Ruby: uploading image problem, getting Internal server error

2012-05-09T13:52:00.002-07:00

There is one thing you need to remember while uploading image using Ruby. You have to read the file in binary mode. Otherwise for some server, you'll get Internal server error. I am giving you an example using the Ruby/Mechanize.

File.open(imgFile, "rb") do|binaryImage|
    content = a.post('http://example.com/uploadImage.php',
            {
                :img        => binaryImage,
                :imgTitle => 'some title'
            });
end

Here,
imgFile is the path to your image.
"rb" used inside file open for reading file as binary mode.

Ruby: OpenSSL::SSL::SSLError with Mechanize

2012-05-09T13:49:00.002-07:00

Have you ever seen an error like below while playing with Ruby/Mechanize with HTTPS links?


`connect': SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed (OpenSSL::SSL::SSLError)

The simple solution to overcome this error by setting SSL verification is false. You can do this like this way with your mechanize agent


a.agent.http.verify_mode = OpenSSL::SSL::VERIFY_NONE

How to install Ruby Mechanize?

2012-05-05T15:43:00.001-07:00

To install the ruby mechanize gem, you can use the gem of ruby. the command is like below.

gem install mechanize

this works for windows, linux, whatever you use.

how to escaping the URL for the Japanese characters

2012-05-01T10:11:00.001-07:00

how to escaping the URL for the Japanese characters? I found a simple way to bypass this problem when i was using shift_jis. example:

$japanese_chars = "チタン";
$encoded_japanese_chars = uri_escape(encode('shiftjis', $japanese_chars));
my $url = "http://www.example.com?param=$encoded_japanese_chars";

Making transparent desktop icon for text.

2012-04-20T03:00:00.002-07:00

Not sure why, but suddenly i found my desktop icon changed from transparent to black. Tried with several methods from internet forums, but nothing worked. Finally the below solution worked for me. I just coppiced from a forum to here at my blog.

Step1: Right click My Computer and choose Properties. Go to Advanced Tab and click
on Settings button under Performance frame and deselect the Use drop shadows for
icon labels on the desktop checkbox and then click OK two times.

Step 2: Start -> Run -> gpedit.msc

Step 3: Go to User Configuration -> Administrative Templates -> Windows Components
-> Windows Explorer. Double click on Turn on Classic Shell and select Enabled option.
Click Apply and OK. Close the Policy Editor.

Step 4: Follow the Step 1 but select the checkbox and click OK.

Step 5: Now go to Desktop to enjoy the Drop-Shadow effect.

Thats it :-)

How to identify the penny pinching buyers

2012-04-08T08:32:00.002-07:00

There are several common dialogs available for the cheap buyers who don't like to pay but want to make you work hard. They don't know how to respect a freelancers. Here are few tips which will help you to identify those idiots.

1) when you'll see a common dialog "those who knows what they are doing...". for a massive difficult work, still they are uttering this fucking bullshit.

2) when you'll see another common dialog "its a busy task, but right now i am busy and want to hire a coder". another fucking bullshit. they are saying this for not paying much, nothing else.

3) a project having highlighted "lowest bid will be the winner". just ignore the project. let him hire the cheapest freelancer. they don't look for quality, so they don't give you respect for your work.

4) china, india, pakistan, romania, when these are the country of the buyer, just kick those assholes. they are middleman, and won't pay much.

that's it so far. make your steps clear before bidding on a project.

The name 'HttpUtility' does not exist in the current context

2012-04-06T09:46:00.002-07:00

I was doing UrlEncode with the HttpUtility library of C# and getting the below error. My .Net version is 3.5;

The name 'HttpUtility' does not exist in the current context

I have resolved this issue by adding the reference of System.Web from Add Reference option(Right click on References -> Add Reference).

Visual Studio: Downgrading from from vs2010 to vs2008

2012-03-30T10:19:00.003-07:00

I was given a project recently made on visual studio 2010. I had to downgrade the project into vs 2008 to work on my side. Here is what i did to accomplish this.

1) open the sln file. and you'll find below two lines


Microsoft Visual Studio Solution File, Format Version 11.00
# Visual Studio 2010

just replace the 11.0 into 10.0 and 2010 into 2008.

Microsoft Visual Studio Solution File, Format Version 10.00
# Visual Studio 2008

2) now open all your project files(*.vbproj). and replace 4.0 with 3.5 from ToolsVersion attribute of xml. For example.

ToolsVersion="3.5"

now load the sln file with your visual studio 2008. it will work.

php: hexadecimal operation over a large number

2012-03-30T10:12:00.002-07:00

Normal decimal to hexadecimal function dechex() doesn't work for a number when its slightly large. For those cases the function base_convert() is useful.


print base_convert(time().'000', 10, 16);

PHP: stop displaying error messages

2012-03-30T10:03:00.002-07:00

i was making a REST api service using php for my clients. During an RSA encrypting processing, a third party library was showing error messages. It was simply garbling my xml outputs. So i need a way to stop the php to display error on page.

ini_set('display_errors', 0);

it worked like a charm for me. This can be resolved from the conf file of apache or php i think. But as it solved for me, i didn't look for that solution.

Python: ImportError: No module named Image

2012-03-19T12:15:00.002-07:00

You are simply getting this because of you somehow not having the Image library of python. Usually this used to be along with python interpreter. Anyway, you can download and install this easily. The link is
www.pythonware.com/products/pil/

After downloading and install, you can use the import Image easily into your python code.

If you are using .tar.gz file, use below commands.

setup.py build
setup.py install

Cannot connect to Gmail: Can't connect to gmail-pop.l.google.com,995: Connection timed out

2012-03-03T07:26:00.002-08:00

If you get this error from your php script, then certainly it's not the issue with your php code. Its issue with your network. Possibly your apache is not allowing the php script to communicate the outside of network.

Cannot connect to Gmail: Can't connect to gmail-pop.l.google.com,995: Connection timed out

To resolve this issue, just connect to your server using SSH and enter the below command to disable SELinux.

setenforce 0

CSharp: replace string using regex pattern

2012-03-01T13:50:00.002-08:00

I use regular expression extensively. So this is my favorite function for replacing a string. Basically code will remove all digits from the given string.

x = Regex.Replace(x, @"\d+", "");

Or everything after starting the digit.
x = Regex.Replace(x, @"\d.*$", "");

CSharp: check whether the file exist or not

2012-03-01T13:47:00.001-08:00

Using the File.Exists of System.IO of C# you can easily check the availability of a file easily.

System.IO.File.Exists(fileName)

CSharp: how to write content to a file

2012-03-01T13:43:00.003-08:00

I prefer two ways to write content into a output file. Below are those

1)System.IO.File.WriteAllLines(@"c:\output.txt", allLines);
Basically you have to combine all your lines into a single string, and then just dump inside the output file.

2) using the StreamWriter of IO.

System.IO.StreamWriter file = new System.IO.StreamWriter(@"C:\output.txt")
now using a loop, just execute the following line inside the loop.
file.WriteLine(line);

CSharp: Exiting from the system

2012-03-01T09:11:00.001-08:00

What is the equivalent of exit() of scripting language like Perl, PHP in C#?
What is the equivalent of System.exit(0) of Java in C#?


Environment.Exit(0);

CSharp: How to read a text file

2012-03-01T07:58:00.002-08:00

In C#, the package System.IO.File will allow you to perform various reading option from a text file.

1) reading the whole content from the file.
string fileContent = System.IO.File.ReadAllText(@"C:\input.txt");
This will read the whole content into the fileContent variable.

2) reading line by line from the text file.
string[] lines = System.IO.File.ReadAllLines(@"C:\input.txt");

CSharp: Equivalent of final

2012-03-01T07:53:00.002-08:00

If you want to declare a variable with final option of Java or const option of C++, that case you have to use the keyword readonly.

An example is :

public readonly int max = 100;

Declaring a two dimensional array

2012-03-01T07:49:00.002-08:00

Unlike any other languages, C# maintains this in a different way. For example a two dimensional array 10x10 can be declared as below:

int[,] twoDimensionalArray = new int[10,10];

inside the brackets, add more commas according to your needs which will just increase a dimension.

Warning: fopen(file.txt): failed to open stream

2012-02-25T04:53:00.002-08:00

In your PHP script, if you get an error like below, then it definitely means that you are missing the read/write like operation parameter.

Warning: fopen(file.txt): failed to open stream: Bad file descriptor in C:\test.php

Lets consider the below code,

$fh_out = fopen($filename, $mode);

Here in your case, you are providing invalid value inside $mode and it is causing the error. change it into anything like 'w', 'r', etc.

Show hidden files and folders is not working

2012-02-24T01:59:00.002-08:00

Everytime I select "Show hidden files and folders" for Tools->Folder Option, it just revert back to hidden mode. Means do not showing hidden files.

I have solved this weird problem by below steps.

1) Click Start –> Run –> and then write "regsvr32 /i browseui.dll" and press ENTER.

It will show a confirmation window. Close it by clicking OK.

2) Click Start –> Run –> and then type "regsvr32 /i shell32.dll" and press ENTER.

It will again show a confirmation window, close it and your problem is solved.

Java: Get the class name of any Object

2011-12-12T19:57:00.000-08:00

Using the getClass() method of any object, you can easily obtain the name of the class of that Object. Below is a simple code snippet to clear the things.


TestClass t = new TestClass();
System.out.println(t.getClass().getName());
// output: TestClass

Java: Converting a byte array into Hexadecimal String

2011-11-29T21:58:00.000-08:00

I have written a method named byteArrayToHexString() which takes a byte array as parameter, and returns the Hexadecimal representation of the byte array. Below is the method.


    public static String byteArrayToHexString(byte []input){
        String string = "";
        if(input == null){
            return string;
        }
        
        for(byte b : input){
            string += Integer.toHexString(Integer.parseInt(Byte.toString(b))).toUpperCase();
        }
        
        return string;
    }

javax.ejb.EJBException: Could not unmarshal method ID

2011-10-25T00:20:00.000-07:00

If you are seeing the following error from your EJB then the solution is really simple.


javax.ejb.EJBException: Could not unmarshal method ID; nested exception is: 
 java.rmi.UnmarshalException: Method not found: 'YOUR_METHOD';

This is because you have written some code but didn't compile or redeployed to your server after compile. So, build/compile your project again and deploy to your server. You'll not see this error again. :-)