Image.GetThumbnailImage 方法

public:
 System::Drawing::Image ^ GetThumbnailImage(int thumbWidth, int thumbHeight, System::Drawing::Image::GetThumbnailImageAbort ^ callback, IntPtr callbackData);

public System.Drawing.Image GetThumbnailImage (int thumbWidth, int thumbHeight, System.Drawing.Image.GetThumbnailImageAbort callback, IntPtr callbackData);

public System.Drawing.Image GetThumbnailImage (int thumbWidth, int thumbHeight, System.Drawing.Image.GetThumbnailImageAbort? callback, IntPtr callbackData);

member this.GetThumbnailImage : int * int * System.Drawing.Image.GetThumbnailImageAbort * nativeint -> System.Drawing.Image

Public Function GetThumbnailImage (thumbWidth As Integer, thumbHeight As Integer, callback As Image.GetThumbnailImageAbort, callbackData As IntPtr) As Image

Image，表示縮圖。

下列程式代碼範例會建立並顯示縮圖影像。 永遠不會呼叫此委派。

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);
}

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

Image如果 包含內嵌縮圖影像，這個方法會擷取內嵌縮圖，並將它調整為所要求的大小。 Image如果 不包含內嵌縮圖影像，此方法會藉由調整主要影像來建立縮圖影像。

當要求的縮圖影像大小大約為 120 x 120 像素時，此方法 GetThumbnailImage 可正常運作。 例如，如果您從具有內嵌縮圖的 要求大型縮圖影像 (300 x 300) Image ，縮圖影像中可能會有明顯的質量遺失。 最好是藉由呼叫 DrawImage 方法來調整主要影像 (，而不是調整內嵌縮圖) 。