delphi 用API实现 窗体半透明效果

procedure TForm1.Button1Click(Sender: TObject);
var
h: HWND;
FormStyle: Integer;
begin
h := self.Handle;
FormStyle := GetWindowLong(h, GWL_EXSTYLE);
SetWindowLong(h, GWL_EXSTYLE, FormStyle or WS_EX_LAYERED);
SetLayeredWindowAttributes(h, 0, 128, LWA_ALPHA);
end;

procedure TForm1.Button2Click(Sender: TObject);
Var
frmRegion, tempRegion: HRGN;
i: Integer;
Arect: TRect;
Begin
frmRegion := 0;
For I:= 0 To ControlCount - 1 Do Begin
Arect := Controls[i].BoundsRect;
OffsetRect( aRect, clientorigin.x - left, clientorigin.y - top );
tempRegion := CreateRectRgnIndirect( aRect );
If frmRegion = 0 Then
frmRegion := tempRegion
Else Begin
CombineRgn( frmRegion, frmRegion, tempRegion, RGN_OR );
DeleteObject( tempRegion );
End;
End;
tempregion :=
CreateRectRgn( 0, 0, Width,
GetSystemMetrics( SM_CYCAPTION )+
GetSystemMetrics( SM_CYSIZEFRAME )+
GetSystemMetrics( SM_CYMENU ) * Ord(Menu <> Nil));

CombineRgn( frmRegion, frmRegion, tempRegion, RGN_OR );
DeleteObject( tempRegion );
SetWindowRgn( handle, frmRegion, true );
end;