Image.GetThumbnailImage Method (Int32, Int32, Image.GetThumbnailImageAbort, IntPtr)
Returns a thumbnail for this Image.
Assembly: System.Drawing (in System.Drawing.dll)
Public Function GetThumbnailImage ( thumbWidth As Integer, thumbHeight As Integer, callback As Image.GetThumbnailImageAbort, callbackData As IntPtr ) As Image
The width, in pixels, of the requested thumbnail image.
The height, in pixels, of the requested thumbnail image.
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.
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 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.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
The following code example creates and displays a thumbnail image. This delegate is never called.
Public Function ThumbnailCallback() As Boolean Return False End Function Public Sub Example_GetThumb(ByVal e As PaintEventArgs) Dim myCallback As New Image.GetThumbnailImageAbort(AddressOf ThumbnailCallback) Dim myBitmap As New Bitmap("Climber.jpg") Dim myThumbnail As Image = myBitmap.GetThumbnailImage(40, 40, myCallback, IntPtr.Zero) e.Graphics.DrawImage(myThumbnail, 150, 75) End Sub
Available since 1.1