[DELPHI]实现windows2000半透明窗体 
function SetLayeredWindowAttributes(hwnd:HWND; crKey:Longint; bAlpha:byte; dwFlags:longint  
):longint; stdcall; external user32;//函数声明 
procedure TForm1.FormCreate(Sender: TObject); 
var l:longint; 
begin 
l:=getWindowLong(Handle, GWL_EXSTYLE); 
l := l Or $80000; 
SetWindowLong (handle, GWL_EXSTYLE, l); 
SetLayeredWindowAttributes(handle, 0, 180, 2); 
end;