ShowMessage(IntToStr(GetSystemMetrics(SM_CYSCREEN)-GetSystemMetrics(SM_CYFULLSCREEN)-GetSystemMetrics(SM_CYCAPTION)));

function GetSystemTaskBarHeight:Integer;
var
R:TRect;
begin
SystemParametersInfo(SPI_GETWORKAREA,0,@R,0);
Result:=Screen.Height-R.Bottom;
end;
//注需要引用ShellAPI单元
function GetTaskBarRect: Integer;
var
TBData: TAPPBARDATA;
begin
TBData.cbSize := SizeOf(TAPPBARDATA);
SHAppBarMessage(ABM_GETTASKBARPOS, TBData);
Result :=Screen.Height-TBData.rc.Top;
end;
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