Büyük harfe çevirme

Function formtyaz(frmy: string): string;
var a:integer; ch:string;
begin
if length(frmy)=0  then
exit;
FOR A:=1 TO LENGTH(FRMY) DO
BEGIN
CASE FRMY[A]  OF
'ı': FRMY[A] := 'I';
'i': FRMY[A] := 'İ';
else
begin
ch:=FRMY[a];
ch:=AnsiUpperCase(ch);
FRMY[a] :=ch[1];
end; end; end;
result:=frmy;
end;

Edit1.Text:=formtyaz(Edit1.Text);

---YADA---

function Buyut(Metin: string): string;
var   a: integer; ch: string;
begin
if length(Metin) = 0 then
exit;
for A := 1 to LENGTH(Metin) do
begin
case Metin[A] of
     'ı': Metin[A] := 'I';
     'i': Metin[A] := 'İ';
else
begin
ch := Metin[a];
ch := ansiUpperCase(ch);
Metin[a] := ch[1];
end; end; end;
result := Metin;
end;

Edit1.Text :=Buyut(Edit1.Text);

---YADA---

procedure TForm1.EditKeyPress(Sender: TObject; var Key: Char);
begin
Key:=BuyukHarf(Key);
end;

Function TForm1.BuyukHarf(Gelen:Char):Char;
var
Tus:String;
begin
Tus:=AnsiUppercase(Gelen);
Result:=Tus[1];
end;