var
abc:blendFunction ;
i:integer;
begin
form1.doublebuffered:=true;
for i:=250 downto 0 do begin
image1.picture.graphic:=Nil;
abc.AlphaFormat:=0;
abc.BlendFlags:=0;
abc.BlendOp:=AC_SRC_OVER;
abc.SourceConstantAlpha:=i;
AlphaBlend(image1.Canvas.Handle,0,0,image1.Width,image1.Height,getdc(0),0,0,image1.Width,image1.Height,abc);
image1.Update;
end;
end;
比较笨的代码