vb6.0做一个半透明窗体（全透）

步骤一：打开VB建立一个窗体Form

步骤二：将窗体背景颜色设为 ：&HFF0000

步骤三：将下面代码粘贴到程序中：

Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" () Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long 
Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" () Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long 
Declare Function SetLayeredWindowAttributes Lib "user32" () Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long 

Private Const WS_EX_LAYERED = &H80000 
Const GWL_EXSTYLE = () Const GWL_EXSTYLE = (-20) 
Private Const LWA_ALPHA = &H2 
Private Const LWA_COLORKEY = &H1 

Sub Form_Load()
        Dim rtn As Long 
        rtn = GetWindowLong(hwnd, GWL_EXSTYLE) 
        rtn = rtn Or WS_EX_LAYERED 
        SetWindowLong hwnd, GWL_EXSTYLE, rtn 
        SetLayeredWindowAttributes hwnd, 0, 100, LWA_ALPHA 
End Sub

运行结果如下：