delphi 截取两个字符之间的内容

function copyBegin2EndStr(begindex, endindex, source: string): string; //截取两个字符之间的内容

var

  n, m: Integer;

begin

  n := Pos(begindex, source);

  m := Pos(endindex, source);

  Result := Copy(source, n + 1, m - n - 1);

end;