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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.

Note   You must create a delegate and pass a reference to the delegate as the callback parameter, but the delegate is not used.

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);
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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