var
S: string;
I, N: Integer;
begin
S := '1234';
N := 3; // 要增加的数值
for I := 1 to Length(S) do
S[I] := Chr(Ord(S[I]) + N); // char进行+3
Caption := S;
end;
procedure TForm1.Button1Click(Sender: TObject);
var I: integer;
str: string;
begin
str := 'ABC';
for I:= 0 to length(str) - 1 do
begin
str[I] := char(ord(str[I])+3);
end;
showmessage(str);
end;