‘----------------------------- ‘使用说明: ‘1.新建一个标准exe工程 ‘2.放置1个CommandButton 控件(使用默认名) ‘3.把下面的代码复制进去就可以了 ‘----------------------------- Option Explicit ‘Transparancy API‘s Private Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hWnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long Private Declare Function UpdateLayeredWindow Lib "user32" (ByVal hWnd As Long, ByVal hdcDst As Long, pptDst As Any, psize As Any, ByVal hdcSrc As Long, pptSrc As Any, crKey As Long, ByVal pblend As Long, ByVal dwFlags As Long) As Long Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long) As Long Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long Private Const GWL_EXSTYLE = (-20) Private Const LWA_COLORKEY = &H1 Private Const LWA_ALPHA = &H2 Private Const ULW_COLORKEY = &H1 Private Const ULW_ALPHA = &H2 Private Const ULW_OPAQUE = &H4 Private Const WS_EX_LAYERED = &H80000 Public Function isTransparent(ByVal hWnd As Long) As Boolean On Error Resume Next Dim Msg As Long Msg = GetWindowLong(hWnd, GWL_EXSTYLE) If (Msg And WS_EX_LAYERED) = WS_EX_LAYERED Then isTransparent = True Else isTransparent = False End If If Err Then isTransparent = False End If End Function Public Function MakeTransparent(ByVal hWnd As Long, ByVal Perc As Integer) As Long Dim Msg As Long On Error Resume Next Perc = 100 If Perc < 0 Or Perc > 255 Then MakeTransparent = 1 Else Msg = GetWindowLong(hWnd, GWL_EXSTYLE) Msg = Msg Or WS_EX_LAYERED SetWindowLong hWnd, GWL_EXSTYLE, Msg SetLayeredWindowAttributes hWnd, 0, Perc, LWA_ALPHA MakeTransparent = 0 End If If Err Then MakeTransparent = 2 End If End Function Public Function MakeOpaque(ByVal hWnd As Long) As Long Dim Msg As Long On Error Resume Next Msg = GetWindowLong(hWnd, GWL_EXSTYLE) Msg = Msg And Not WS_EX_LAYERED SetWindowLong hWnd, GWL_EXSTYLE, Msg SetLayeredWindowAttributes hWnd, 0, 0, LWA_ALPHA MakeOpaque = 0 If Err Then MakeOpaque = 2 End If End Function ‘透明 Private Sub Command1_Click() MakeTransparent Me.hWnd, 120 ‘这里的120是透明度,在0~255之间取值 End Sub
原文:http://www.cnblogs.com/mengkun/p/4280301.html