Question

vb6.0透明窗体遇到的问题

Option Explicit
Private Declare Function createcompatiblebitmap Lib "gdi32" (ByVal hdc As Long, ByVal nwidth As Long, byvalnheight As Long) As Long
Private Declare Function selectobject Lib "gd32" (ByVal hdc As Long, ByVal hobject As Long) As Long

Private Sub Form_Load()
Dim bitmap
Me.AutoRedraw = True
bitmap = createcompatiblebitmap(Me.hdc, 0, 0)
selectobject Me.hdc, bitmap

End Sub

Private Sub Label1_DblClick()
End
End Sub
运行时提示
实时错误'453'
找不到dll入口点 createcompatiblebitmap in gdi32
请详细说明错误地方
怎么做会实现窗体透明
用你的是透明了 可是不能对其进行操作
上面的label text都不能操作连关闭都不能用
有办法解决一下吗

Answer 1

试试这个吧。
Const LWA_COLORKEY = &H1
Const LWA_ALPHA = &H2
Const GWL_EXSTYLE = (-20)
Const WS_EX_LAYERED = &H80000
Const WS_EX_TRANSPARENT As Long = &H20&
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 Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hWnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long

Private Sub Form_Load()
Dim Ret As Long
Ret = GetWindowLong(Me.hWnd, GWL_EXSTYLE)
Ret = Ret Or WS_EX_LAYERED Or WS_EX_TRANSPARENT
SetWindowLong Me.hWnd, GWL_EXSTYLE, Ret
SetLayeredWindowAttributes Me.hWnd, 0, 200, LWA_ALPHA
End Sub

呵呵，再试试这个：
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 Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
'其中hwnd是透明窗体的句柄，crKey为颜色值，bAlpha是透明度，取值范围是[0,255]，dwFlags是透明方式，可以取两个值：当取值为LWA_ALPHA时，crKey参数无效，bAlpha参数有效；当取值为LWA_COLORKEY时，bAlpha参数有效而窗体中的所有颜色为crKey的地方将变为透明－－这个功能很有用：我们不必再为建立不规则形状的窗体而调用一大堆区域分析、创建、合并函数了，只需指定透明处的颜色值即可，哈哈哈哈！请看具体代码。
Private Const WS_EX_LAYERED = &H80000
Private Const GWL_EXSTYLE = (-20)
Private Const LWA_ALPHA = &H2
Private Const LWA_COLORKEY = &H1

'代码: 一个半透明窗体
Private 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, 200, LWA_ALPHA
End Sub