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Image.GetThumbnailImage Method

Returns a thumbnail for this Image.

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

public Image GetThumbnailImage(
	int thumbWidth,
	int thumbHeight,
	Image..::.GetThumbnailImageAbort callback,
	IntPtr callbackData
)

Parameters

thumbWidth
Type: System.Int32

The width, in pixels, of the requested thumbnail image.

thumbHeight
Type: System.Int32

The height, in pixels, of the requested thumbnail image.

callback
Type: System.Drawing.Image.GetThumbnailImageAbort

A Image.GetThumbnailImageAbort delegate. In GDI+ version 1.0, the delegate is not used. Even so, you must create a delegate and pass a reference to that delegate in this parameter.

callbackData
Type: System.IntPtr

Must be Zero.

Return Value

Type: System.Drawing.Image
An Image that represents the thumbnail.

If the Image contains an embedded thumbnail image, this method retrieves the embedded thumbnail and scales it to the requested size. If the Image does not contain an embedded thumbnail image, this method creates a thumbnail image by scaling the main image.

The GetThumbnailImage method works well when the requested thumbnail image has a size of about 120 x 120 pixels. If you request a large thumbnail image (for example, 300 x 300) from an Image that has an embedded thumbnail, there could be a noticeable loss of quality in the thumbnail image. It might be better to scale the main image (instead of scaling the embedded thumbnail) by calling the DrawImage method.

The following code example creates and displays a thumbnail image. This delegate is never called.

public bool ThumbnailCallback()
 {
 return false;
 }
 public void Example_GetThumb(PaintEventArgs e)
 {
 Image.GetThumbnailImageAbort myCallback =
 new Image.GetThumbnailImageAbort(ThumbnailCallback);
 Bitmap myBitmap = new Bitmap("Climber.jpg");
 Image myThumbnail = myBitmap.GetThumbnailImage(
 40, 40, myCallback, IntPtr.Zero);
 e.Graphics.DrawImage(myThumbnail, 150, 75);
 }

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
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