Graphics::FromImage Method (Image^)

 

Creates a new Graphics from the specified Image.

Namespace:   System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

public:
static Graphics^ FromImage(
	Image^ image
)

Parameters

image
Type: System.Drawing::Image^

Image from which to create the new Graphics.

Return Value

Type: System.Drawing::Graphics^

This method returns a new Graphics for the specified Image.

Exception Condition
ArgumentNullException

image is null.

Exception

image has an indexed pixel format or its format is undefined.

If the image has an indexed pixel format, this method throws an exception with the message, "A Graphics object cannot be created from an image that has an indexed pixel format." The indexed pixel formats are shown in the following list.

You can save the indexed image as another format by using the Save(String^, ImageFormat^) method and then retrieve a Graphics object for the new image.

This method also throws an exception if the image has any of the following pixel formats.

You should always call the Dispose method to release the Graphics and related resources created by the FromImage method.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following action:

  • Creates an Image from a graphics file SampImag.jpg in the example folder.

  • Creates a Graphics from the Image.

  • Alters the image by filling a rectangle within it.

  • Draws the Image to the screen.

  • Releases the created Graphics.

public:
   void FromImageImage( PaintEventArgs^ e )
   {
      // Create image.
      Image^ imageFile = Image::FromFile( "SampImag.jpg" );

      // Create graphics object for alteration.
      Graphics^ newGraphics = Graphics::FromImage( imageFile );

      // Alter image.
      newGraphics->FillRectangle( gcnew SolidBrush( Color::Black ), 100, 50, 100, 100 );

      // Draw image to screen.
      e->Graphics->DrawImage( imageFile, PointF(0.0F,0.0F) );

      // Dispose of graphics object.
      delete newGraphics;
   }

.NET Framework
Available since 1.1
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