VB实现半透明或者部分透明窗体


        Windows2000已经出了n年多了,就先介绍一下Windows2000特有的API吧!! AnimateWindow是一个窗口打开和关闭时产生动画效果的新函数,因为是一个新的函数, 所以在 API Viewer中是找不到的,必需自己定义:

   Public Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long

  '具体可以使用的常量及其用法

  Const LWA_ALPHA=&H2     '表示把窗体设置成半透明样式
  Const LWA_COLORKEY=&H1     '表示不显示窗体中的透明色
 
   
  具体例子

  程序代码

  Module1

Public Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
Public Const WS_EX_LAYERED = &H80000
Public Const GWL_EXSTYLE = (-20)
Public Const LWA_ALPHA = &H2
Public Const LWA_COLORKEY = &H1
Public Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long
Public Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long


  Form1

Private Sub Form_Load()
Dim rtn As Long

  rtn = GetWindowLong(Me.hwnd, GWL_EXSTYLE)    '取的窗口原先的样式
rtn = rtn Or WS_EX_LAYERED     '使窗体添加上新的样式WS_EX_LAYERED
SetWindowLong Me.hWnd, GWL_EXSTYLE, rtn    '把新的样式赋给窗体

  SetLayeredWindowAttributes me.hwnd, 0, 192, LWA_ALPHA

    '把窗体设置成半透明样式,第二个参数表示透明程度
    '取值范围0--255,为0时就是一个全透明的窗体了

  End Sub


  第二种使用方法

  SetLayeredWindowAttributes Me.hWnd, &H0, 0, LWA_COLORKEY
    '表明不显示窗体中的透明色
    '而第二个参数表示透明色为黑色,并且你可以用RGB函数来指定颜色值

源码下载:

posted @ 2008-06-08 16:03  jetz  阅读(2603)  评论(0编辑  收藏  举报