获取桌面窗口图象

 

     Windows提供了一个API函数GetDesktopWindow,该函数返回桌面窗口的设备描述。因此利用它就可以轻松获取桌面窗口的图象。

参见下例：

>>步骤1----建立新工程。

>>步骤2----编写如下代码：

 

Private Declare Function GetDesktopWindow Lib "user32" () As Long

Private Declare Function GetDC Lib "user32" (ByVal hwnd As Long) _

    As Long

Private Declare Function BitBlt Lib "gdi32" _

    (ByVal hDestDC As Long, ByVal x As Long, _

    ByVal y As Long, ByVal nWidth As Long, _

    ByVal nHeight As Long, ByVal hSrcDC As Long, _

    ByVal xSrc As Long, ByVal ySrc As Long, _

    ByVal dwRop As Long) As Long

 

Private Sub Form_Load()

    Dim lDesktop As Long

    Dim lDC As Long

 

    Form1.AutoRedraw = True

    Form1.ScaleMode = 1

    lDesktop = GetDesktopWindow() 

    lDC = GetDC(lDesktop) 

    BitBlt Me.hDC, 0, 0, Screen.Width, Screen.Height, lDC, _

        0, 0, vbSrcCopy 

End Sub

 

>>步骤3----编译运行，看看大功告成了吧！

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