Word count statistics like in MS Word on Delphi

Question

Could you explain how to count words in TMemo and show the results in TLabet or TEdit? Is it possible? Also I would like to know how count similar words (duplicate words) quantity. Thank you. PS: how can i found words density in the text? For example: word "dog" appears three times in the text. Word number of the text is 100. Therefore density of the word "dog" is 3%. (3/100 * 100%).

Answer 1

For the first part (uses Character),

function CountWordsInMemo(AMemo: TMemo): integer;
var
  i: Integer;
  IsWhite, IsWhiteOld: boolean;
  txt: string;
begin
  txt := AMemo.Text;
  IsWhiteOld := true;
  result := 0;
  for i := 1 to length(txt) do
  begin
    IsWhite := IsWhiteSpace(txt[i]);
    if IsWhiteOld and not IsWhite then
      inc(result);
    IsWhiteOld := IsWhite;
  end;
end;

For the second part,

function OccurrencesOfWordInMemo(AMemo: TMemo; const AWord: string): integer;
var
  LastPos: integer;
  len: integer;
  txt: string;
begin
  txt := AMemo.Text;
  result := 0;
  LastPos := 0;
  len := Length(AWord);
  repeat
    LastPos := PosEx(AWord, txt, LastPos + 1);
    if (LastPos > 0) and
      ((LastPos = 1) or not IsLetter(txt[LastPos-1])) and
      ((LastPos + len - 1 = length(txt)) or not IsLetter(txt[LastPos+len])) then
      inc(result);
  until LastPos = 0;
end;

function DensityOfWordInMemo(AMemo: TMemo; const AWord: string): real;
begin
  result := OccurrencesOfWordInMemo(AMemo, AWord) / CountWordsInMemo(AMemo);
end;