//声明:GetSystemDirectory(  lpBuffer: PChar; {缓冲区}  uSize: UINT      {缓冲区大小}): UINT;           {返回实际长度}         //举例:var  arr: array[0..MAX_PATH] of Char;  num: UINT;begin  num := GetSystemDirectory(arr, MAX_PATH);  ShowMessage(arr);           {C:\WINDOWS\system32}  ShowMessage(IntToStr(num)); {19}end;