String buchstabenweise in array einlesen

[Bjoerk]

Vermutlich meint dein Lehrer lediglich das:

Delphi-Quellcode:

type
  TCharArray = array of Char;


function LowerCaseChar (const C: char): char;
begin
  Result:= C;
  if (Result in ['A'..'Z', 'Ä', 'Ö', 'Ü']) then
    Inc(Byte(Result), 32);
end;


function FindChar (const S: TCharArray; const C: char): integer;
var
  I: integer;
begin
  Result:= 0;

  for I:= 0 to Length(S)-1 do
    if S[I] = C then Inc(Result);
end;


procedure TForm1.Edit2Change(Sender: TObject);
var
  I, L1, L2, N: integer;
  C: char;
  S: TCharArray;
begin
  Label1.Caption:= '';

  L1:= Length(Edit1.Text);
  L2:= Length(Edit2.Text);

  if ((L1 > 0) and (L2 > 0)) then
  begin
    SetLength(S, L1);

    for I:= 1 to L1 do
      S[I-1]:= LowerCaseChar(Edit1.Text[I]);

    C:= LowerCaseChar(Edit2.Text[1]);

    N:= FindChar(S, C);
    Label1.Caption:= 'Buchstabe ' + C + ' kommt ' + IntToStr(N)+' mal vor.';

    SetLength(S, 0);
  end;
end;