写个函数也可以

  function IsMobileNumber( num:string ):boolean;

  begin

    Result:=False;

    if length( trim( Num ) ) <> 11 then Exit;

    if ( ( copy( num, 1, 2) <> '13' ) and ( copy( num , 1, 2) <> '15' ) ) then Exit;

    try

      StrToInt( copy( num, 3, 9 ) );

      Result:=True;

    except

    end;

  end;