急。chr 与ord的运用！

[itfly]

procedure TForm1.FormCreate(Sender: TObject);

begin
Edit1.Text:="58D2F155"
end;

procedure TForm1.Button1Click(Sender: TObject);
var Xl:integer;
i:integer;
y:integer;
s:string;
aa:string ;
begin
s:=edit1.Text;
Xl:=Length(s);
for i :=1 to xl do
begin
aa:= copy(s,i,1);
y:=y+ord(aa[1]);
end;
edit2.Text:=inttostr(y);
label5.Caption:=inttostr(xl);//得到其ASCII值！
end;

procedure TForm1.Button2Click(Sender: TObject);
var ss:string;
m:integer;
aar:char;
yy:String;
j:integer;
begin
ss:=edit2.Text;
m:=Length(ss);
for j:=1 to m do
begin
aar:=chr(byte(edit2.text[j]));
yy:=yy+aar;
end;
edit3.Text:=yy;
label5.Caption:=edit2.Text[j];//返回得到edit1.text中的值，但得不到。我错在那儿了？！
end;

[jacky_shen]

Chr(65) ==> A
Returns the character for a specified ASCII value.

Ord('A') ==> 65
Returns the ordinal value of an ordinal-type expression.

[WWWWA]

aar:=chr(byte(edit2.text[j]));这一句检查一下

[itfly]

???怎么检查、?