205.txt

介绍VB里的各种控件的使用方法,窗口控制,图像编程以及OCX等内容,还提供了一个API集供参考.

制造出透明的Form 
注释：form上有Command1, command2两个Button并事先设定form之BorderStyle = 0

Option Explicit
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
Const GWL_EXSTYLE = (-20)
Const WS_EX_TRANSPARENT = &H20&
Private PreValue As Long

Private Sub Command2_Click() 注释：还原变成不透明
Call SetWindowLong(Me.hwnd, GWL_EXSTYLE, PreValue)
Me.Hide
Me.Show
End Sub

Private Sub Form_Load()
Dim i As Long

i = GetWindowLong(Me.hwnd, GWL_EXSTYLE)
注释：变成透明的Form
PreValue = SetWindowLong(Me.hwnd, GWL_EXSTYLE, i Or WS_EX_TRANSPARENT)
Me.Show
DoEvents
Command1.Refresh 注释：令Command1可见
Command2.Refresh 注释：令Command2可见
End Sub