First thing you should do is to reference the System.IO namespace.

All the classes that will help you handle files are located in this namespace.

using System.IO;

How to create a file and edit it?

You can create a file like this:

string path = @"C:\test.txt";
File.Create(path);

This will create a file “test.txt” in C: drive. File.Create() method can be used to create all kind of files. It returns a FileStream instance which you can use to work with the new file. I mean you can also write the above code as FileStream stream = File.Create(path);

Remember, it is not a good practice to use File.Create() method without saving the FileStream reference in a variable. Because otherwise you won’t be able to close the stream and you will get this error if you work with the file:

The process cannot access the file because it is being used by another process.

Whenever you get that error check your code for streams that are not closed. Always close a stream using the Close() method when you are done with it. Or a recommended way is to use the using Statement (I’ve used it below).

Okay, we have created a file but it is empty which makes it useless. Let’s add something to it:

using (FileStream stream = File.Create(path))
{
   Byte[] text = new UTF8Encoding(true).GetBytes("Hello, World.");
   stream.Write(text, 0, text.Length);
}

FileStream is not the best choice if you adding only text to a file. For more on the text files check the next part.

How to create a text file or open a text file and edit it?

Here we will use the File.CreateText() method to create the file. It returns a StreamWriter instance which allows you to write text to the file.

string path = @"C:\abc.txt";

// This makes a new file and then opens it for writing
using (StreamWriter writer = File.CreateText(path))
{
   // Write a string to the file
   writer.Write("Welcome.");

   // Write a line
   writer.WriteLine("Hello, World");
   writer.WriteLine("What's up?");
}

// Open an existing file and write to it
using (StreamWriter writer = File.Open(@"C:\xyz.txt"))
{
   //... write text
}

// To append to an existing file
using (StreamWriter writer = File.AppendText(@"C:\xyz.text"))
{
   //... write text
}

How to copy, move, delete and rename a file?

To move or copy a file you can use File.Copy() and File.Move() methods.

// Current path of the file
string path = @"C:\abc.txt";

// New path for the file
string newPath  = @"F:\abc.txt";

// To avoid errors we shoud make sure the file exists.
if (File.Exists(path))
{
   // Copy the file
   File.Copy(path, newPath);

   // Move the file
   File.Move(path, newPath);

   // Delete the file
   File.Delete(path);
}

To rename a file we will use the File.Move() method:

// You use the same path but only rename the filename
string currentName = @"C:\abc.txt";
string newName  = @"C:\xyz.txt";

File.Move(currName, newName);

If you have any questions please don’t hesitate to post a comment.

In this tutorial I will teach you how to make a simple game. This tutorial is mainly aimed at users who are new to Unity. So let’s begin.

First off create a new project if you haven’t already made one.

Right-click inside your Project tab and click Import Package > Character Controller. Click on “none” at the bottom left and scroll down to the bottom. Under Scripts tick “MouseLook.cs”. This will import the MouseLook script. It will help us rotate the camera around using mouse movement.

Now that we’ve got the MouseLook script let’s attach it to our camera. Select the MainCamera in the Hierarchy and in the top menu go to Component > Camera-Control > MouseLook. Viola! Now if you play the game you can rotate the camera around by moving the mouse but our scene is empty and all you see is a blank blue background. Let’s design a simple level.

In the top menu go to GameObject > Create Other > Plane. In the Inspector set its x/y/z position to “0″ and set its x/y/z scale to “2″, so our camera can see it. Hit Play and now you can see that if you move the mouse the camera will rotate!

But its pretty dark in here, isn’t it? Let’s add a light so we can see things a little better.

Go to GameObject > Create Other > Point Light and use the following values:

Play the game and you’ll see its not dark anymore.

So, now we’ve got a simple level and we can rotate the Camera using the mouse! But that’s not interesting. Let’s add some stuff we can interact with.

Go to GameObject > Create Other > Cube and in the Inspector set its x/y/z position to “X: 0, Y: 0.5, Z: 0″. Next go to Component > Physics > Rigidbody to make it a Rigidbody. Now it will be affected by gravity and it will respond to collisions with real time Physics etc. You can read more about Rigidbodies at the Unity Documentation.

Go to Edit > Duplicate and make 5 copies of it so you’ll have 6 cubes in your scene. Position them like this:

Now we’re gonna make the player throw a ball. Go to GameObject > Create Other > Sphere. We want the ball to be affected by gravity and want it to collide with cubes. So add a Rigidbody to it by going to Component > Physics > Rigidbody. Position the ball right in front of the cubes but not too close the cubes.

To make the player throw the ball we’ll need a script. In the Project tab click on Create > Javascript, name it “ThrowScript”. Double click to edit the script and use this code:

// This variable will contain a refernce the ball
var ball : GameObject;

// Speed of the ball
var speed : float = 800f;

function Update ()
{
	// If the Space key is pressd, apply force on the ball in z-axis (forward)
	if(Input.GetKeyDown("space"))
		ball.rigidbody.AddForce(0, 0, speed);
}

We’re almost done. In the Project tab drag the ThrowScript and drop it over the MainCamera in the Hierarchy to attach it to the camera. All we need to do now is to tell the script which ball to use. Select the MainCamera and scroll down to the ThrowScript in the Inspector and drag and drop the Sphere into the Ball variable.

That’s it! Our simple game is now finished. Play the game and press space and you’ll see how the cubes react when the balls collides with them.

If you have any questions or tutorial requests post a comment below.

I am currently working on an this game. I will post Unity tutorials in the next few weeks.

If I had time I would make a video serious which will teach how to make a game like that.

Following are the features of this application:

• Open / Save images.
• Convert images.
• Rotate Images.
• All popular image formats are supported.

Let’s get started!

Setting up the Designer

For this application you will need an openFileDialog, saveFileDialog, pictureBox and a few buttons.

1. Add openFileDialog and saveFileDialog to the form.
2. Use this filter for the openFileDialog and saveFileDialog: ” JPEG File|*.jpg|GIF File|*.gif|PNG File|*.png|BMP File|*.bmp “
3. Add 4 buttons (refer to the image above). Name the buttons just like I’ve did in that image.
4. Set the “Enabled” property for “Save” button to “False”. And set “Visible” to “False” for “RotateClockwise” and “RotateCounterclockwise” buttons.
5. Add a pictureBox and place it under the buttons (refer to the image above).

That’s it. Now lets get on with the code.

The Code

First of all, add this code to the very top of your form:

using System.Drawing.Imaging;

Declare these methods after the “public Form1() { ….” method:

// This method will be used to save the image

private void saveImage(string ext)
{
   ImageFormat format = null;

   if(ext == ".gif")
      format = ImageFormat.Gif;
   else if(ext == ".jpg" || ext == ".jpeg")
      format = ImageFormat.Jpeg;
   else if(ext == "png")
      format = ImageFormat.Png;
   else if(ext == ".bmp")
      format = ImageFormat.Bmp;

   pictureBox1.Image.Save(saveFileDialog1.FileName, format);
}

// This method will be used for rotating the image.
private void rotateImage(int angle)
{
   Bitmap img = new Bitmap(pictureBox1.Image);

   // 0 = Clockwise, 1 = counter-clockwise
   if (angle == 0)
      img.RotateFlip(RotateFlipType.Rotate90FlipNone);
   else if (angle == 1)
      img.RotateFlip(RotateFlipType.Rotate90FlipXY);

   pictureBox1.Size = img.Size;
   pictureBox1.Image = img;
}

Double-click the “Open” button to add the “Click()” event for it and use this code:

private void openBtn_Click(object sender, EventArgs e)
{
   DialogResult result = openFileDialog1.ShowDialog();

   if (result == DialogResult.OK)
   {
      Image img = Image.FromFile(openFileDialog1.FileName);

      // Assigns the opened image to picturebox.
      pictureBox1.Image = img;

      // Makes the pictureBox width/height same as the opened image.
      pictureBox1.Width = img.Width;
      pictureBox1.Height = img.Height;
   }

   // Enables the Save button.
   saveBtn.Enabled = true;

   // Shows the RotateClockwise and Counterclockwise buttons.
   rotateClockwise.Show();

   rotateCounter.Show();
 }

Double-click the Save button and use this code:

private void saveBtn_Click(object sender, EventArgs e)
{
   DialogResult res = saveFileDialog1.ShowDialog();

   if (res == DialogResult.OK)
   {

      // Extracts the extension from the opened file.
      string ext = System.IO.Path.GetExtension(saveFileDialog1.FileName);

      ext = ext.ToLower();
      saveImage(ext);
   }
}

Double-click the RotateClockwise button and use this code:

private void rotateClockwise_Click(object sender, EventArgs e)
{
   // Calls the rotateImage method and passes the parameter "0"
   // Refer to the rotateImage method to see how it works.
   rotateImage(0);
}

And lastly, double-click the Rotate Counterclockwise button and use this code:

 private void rotateCounter_Click(object sender, EventArgs e)
{
   // 1 = counter-clockwise
   rotateImage(1);
}

That’s it! We are done.

Source Code

ImageViewer Source – Download Now (42 Kb)

Buy domain names

Following are the features of this class:

• Take screenshot of the whole screen
• Take screenshot of a particular area using a Rectangle
• Copy the screenshot to Clipboard.
• Save the screenshot straight after it is captured.
• All popular image formats are supported.

How to use?

To import this class into your C# project all you have to do is to drag and drop the “ScreenCapture.cs” file into your project.

It is very simple to use this class. Here’s an overview of all the features:

// Add this code to the top of your code
// i.e: add it above "public Form1() { ......"

SC.ScreenCapture SC = new SC.ScreenCapture();

// To take a screenshot of the whole screen
// Use this code:

SC.CaptureScreen();

// If you want to save the screenshot straight after it is taken
// Use this code:
// Replace "C:\\screenshot.jpg" with your own path

SC.CaptureScreen(@"C:\screenshot.jpg");

// To take screenshot of a particular area
// Use this code:
// Replace "Rect" with a Rectangle

SC.CaptureRectangle(Rect);

// To save the screenshot straight after it is taken
// Use this code:
// Replace "C:\screenshot-rect.jpg" with your own path and "Rect" with a rectangle.

SC.CaptureRectangle(Rect, "C:\\screenshot-rect.jpg");

// Note: Use the code below after you've taken a screenshot.
// To copy the screenshot to Clipboard
// Use this code

SC.CopyToClipboard();

The above instructions showed you all the features this class offers. However, if you want to see this class in acton. Then I’ve made a simple application for you, which uses this class. Download the class alone or the sample application below:

Dowload the ScreenCapture class and a sample application

ScreenCapture Class – Download Now (1 Kb)

Sample Application – Download Now (46 Kb)

The solution for that was to check for internet connection before checking for updates. If connected then check for updates otherwise show an error.

Checking for the state of internet connection is very simple. Let’s get started.

Firstly, import System.Runtime.InteropServices namespace. Add this to the top of your code:

using System.Runtime.InteropServices;

Then use this code for checking connection state:

For C# Beginners: Add this code above or below public Form1() { … }

// API Method
[DllImport("wininet.dll")]
private extern static bool InternetGetConnectedState(out int Description, int ReservedValue);

// A method for checking the state
public static bool IsConnected()
{
    int Description;
    return InternetGetConnectedState(out Description, 0);
}

Now you can use the above method to check for connection before doing anything that requires internet connection.

Example use:

// If internet connection is active
if (IsConnected())
{
    // do something
}
else
{
   MessageBox.Show("Please connect to the internet.");

If you have any questions please don’t hesitate to post a comment.

For cropping an image in C# & VB.NET we can use the Graphics class. We’ll use a method (or function in VB.NET) which will take 2 parameters, a source image and a rectangle of the section that should be cropped.  Let’s code!

The Code

C#:

public Bitmap CropImage(Bitmap source, Rectangle section)
{

 // An empty bitmap which will hold the cropped image
 Bitmap bmp = new Bitmap(section.Width, section.Height);

 Graphics g = Graphics.FromImage(bmp);

 // Draw the given area (section) of the source image
 // at location 0,0 on the empty bitmap (bmp)
 g.DrawImage(source, 0, 0, section, GraphicsUnit.Pixel);

 return bmp;
}

// Example use:

Bitmap source = new Bitmap(@"C:\tulips.jpg");
Rectangle section = new Rectangle(new Point(12, 50), new Size(150, 150));

Bitmap CroppedImage = CropImage(source, section);

VB.NET

Function CropImage(ByVal source As Bitmap, ByVal section As Rectangle) As Bitmap

 ' An empty bitmap which will hold the cropped image
 Dim bmp As New Bitmap(section.Width, section.Height)

 Dim g As Graphics = Graphics.FromImage(bmp)

 ' Draw the given area (section) of the source image
 ' at location 0,0 on the empty bitmap (bmp)
 g.DrawImage(source, 0, 0, section, GraphicsUnit.Pixel)

 return bmp
End Function

' Example use:

Dim source As New Bitmap("C:\tulips.jpg")
Dim section As New Rectangle(new Point(12, 50), new Size(150, 150))

Dim CroppedImage As Bitmap = CropImage(source, section)

Explanation

The above code will work perfectly but it seems confusing, doesn’t it? You might have been wondering how it works. Well…

We first make an empty bitmap of the same width/height as the section rectangle. This bitmap will hold the cropped image. We use the section rectangle’s width/height because it determines the size of the cropped image. Then we use the Graphics class’s DrawImage() method (function) for the cropping. It draws the given area (section) of the source image on the empty bitmap and that’s it. The empty bitmap now holds the cropped image.

Source Code

Download Source Code for C#

Download Source Code for VB.NET

If you have any questions, don’t hesitate to post a comment.

Thanks

Fortunately, textbox has a built-in autocomplete feature! We don’t have to do any coding.

You can either set it up from the Designer (if you are using Visual Studio or #Develop) or do it via code. It is simple both ways. Lets do it!

Setting up AutoComplete

For setting up autocomplete you’ll have to use three properties of the TextBox class — AutoCompleteSource, AutoCompleteCustomSource and AutoCompleteMode. Here’s an explanation of these properties:

AutoCompleteSource is the source of the suggestions. You can assign it CustomSource if you want to use custom suggestions or use other auto sources like FileSystem, HistoryList etc. Below are all the available sources:

• FileSystem: This will show suggestions from the file system i.e files stored on the computer. Like if you write “C:\” it’ll show all the files stored on C: drive.
• FileSystemDirectories: This is same as FileSystem but it shows directory names instead of file names.
• HistoryList: This will show URLs from Internet Explorer’s history.
• RecentlyUsedList: A list of recently used applications, folders, and URLs (from internet explorer).
• AllUrl: This specifies an equivalent of HistoryList and RecentlyUsedList as the source.
• AllSystemSources: Specifies an equivalent of AllUrl and FileSystem as the source.

AutoCompleteModes are of 3 types. Suggest, Append and SuggestAppend:

• Suggest will show suggestions in a drop-down as the user types.
• Append will auto complete as you type. Like if you write “Goo” it’ll automatically make it “Google”.
• SuggestAppend will do both Suggest/Append.

AutoCompleteCustomSource is collection of custom suggestions. It will be used when you assign “CustomSource” as “AutoCompleteSource”.

Okay enough explanations. Lets make an autocomplete textbox now.

Using Designer:

If you are using the Designer, then all you have to do is to select your TextBox and change those three properties (explained above). For instance, if you want to use custom suggestions then use “CustomSource” and add the custom suggestions to “AutoCompleteCustomSource” (don’t forget to set up AutoCompleteMode). Debug your project and see! Its that easy . Don’t forget that you can also use all the other sources like FileSystem, HistoryList etc.

Via Coding:

Here’s an example:

// List of custom suggestions
string[] suggestions = new string[] {
"Google",
"Google Images",
"Yahoo",
"Youtube"
};

// Use the AutoCompleteMode that suits you.
textBox1.AutoCompleteMode = AutoCompleteMode.Suggest;

// Since we are using custom suggestions you
// should use this source.
// Use the other non-custom sources if you
// don't want to use custom suggestions.
textBox1.AutoCompleteSource = AutoCompleteSource.CustomSource;

// And finally add the above suggestions to the CustomSource
textBox1.AutoCompleteCustomSource.AddRange(suggestions);

That’s it.

If you have any questions, don’t hesitate to post a comment.

Here’s a boolean method that checks whether a form is open or not :

private bool CheckForm(Form form)
{
   foreach (Form f in Application.OpenForms)
       if (form == f)
          return true;

 return false;
}

Example use:

// if form2 is not running

if (!CheckForm(form2))
  {
      // do something
  }

Thanks.

If you have any questions, don’t hesitate to post a comment.

To show you how autoclick/autofill works we’ll make a simple Google AutoSearch Bot.

So lets begin…

First of all, add a webBrowser control to your form. Set its “Url” property to “www.google.com”.

Now we’ll add two methods SetText() and ClickButton(). SetText() method will automatically fill a textBox and the ClickButton() will click the submit button.

Since we are making a Google AutoSearch Bot we need to find what’s the name of the Google search textBox and the submit button. To find these, visit Google.com from your browser and view the page source.

Here’s the code for the SetText() method:

// Set value for the attribute that has the name (attName)

void SetText(string attribute, string attName, string value)
 {

 // Get a collection of all the tags with name "input";

 HtmlElementCollection tagsCollection = webBrowser1.Document.GetElementsByTagName("input");

 foreach (HtmlElement currentTag in tagsCollection)
 {

 // If the attribute of the current tag has the name attName

   if (currentTag.GetAttribute(attribute).Equals(attName))

 // Then set its attribute "value".

   currentTag.SetAttribute("value", value);
 }
}

And now the code for the ClickButton() method:

// Click the button whose attribute has a name "attName"

 void ClickButton(string attribute, string attName)
 {
    HtmlElementCollection col = webBrowser1.Document.GetElementsByTagName("input");

    foreach (HtmlElement element in col)
    {
      if (element.GetAttribute(attribute).Equals(attName))
      {

      // Invoke the "Click" member of the button
      element.InvokeMember("click");
      }
    }
 }

Now that the main methods are added we can now tell the bot what to do .

Declare “bool searched = false” at Class-level (i.e add it above pulic Form1() {……). We’ll use it to check whether we have already searched or not.

Add DoucmentComplete event for the webBrowser. DocumentComplete event is fired when the page is loaded completely.

Use this code:

Note: The name of the Google search textBox is “q” and the submit buttons is “btnG”.

private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
 {

 // Check if already searched

 if(searched == false)
 {

 // Set the text to "Search Text Here" of the textBox whose "name" attribute is "q";

 SetText("name", "q", "Search Text Here");

 // Click the button whose name attribute is "btnG"

 ClickButton("name", "btnG");

 // Since we have already searched, set it to true

 searched = true;

 }
 }

That’s it! Debug the project and watch the bot

If you have any questions don’t hesitate to post a comment.

Thanks