Create XNA sprite on the fly from an image

I have an image, let's says a .png, that is uploaded by the user. This image has a 开发者_开发问答fixed size, let's say 100x100.

I would like to create 4 sprites with this image.

One from (0,0) to (50,50)

Another from (50, 0) to (100, 50)

The third from (0, 50) to (50, 100)

The last from (50, 50) to (100, 100)

How can I do that with my prefered C# ?

Thanks in advance for any help

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To create a texture from a PNG file, use the Texture2D.FromStream() method (MSDN).

To draw the different sections of the texture, use the sourceRectangle parameter to an overload of SpriteBatch.Draw that accepts it (MSDN).

Here's some example code:

// Presumably in Update or LoadContent:
using(FileStream stream = File.OpenRead("uploaded.png"))
{
    myTexture = Texture2D.FromStream(GraphicsDevice, stream);
}

// In Draw:
spriteBatch.Begin();
spriteBatch.Draw(myTexture, new Vector2(111), new Rectangle( 0,  0, 50, 50), Color.White);
spriteBatch.Draw(myTexture, new Vector2(222), new Rectangle( 0, 50, 50, 50), Color.White);
spriteBatch.Draw(myTexture, new Vector2(333), new Rectangle(50,  0, 50, 50), Color.White);
spriteBatch.Draw(myTexture, new Vector2(444), new Rectangle(50, 50, 50, 50), Color.White);
spriteBatch.End();