Replace All

function replaceAll(haystack: string; needle:string; cod:string):string;
begin
  var s:string = haystack;
  var proc:string = '';
  var p,len:integer;
  len:=length(needle);
  while(length(s)>0) do begin
    p:=s.IndexOf(needle);
    if (p=0) then begin proc+=s; break; end;
    if (p>1) then proc+=copy(s,1,p-1);
    proc+=cod;
    if (p+len)>length(s) then
      s:='' else
      s:=copy(s,p+len,length(s)-p-len);
  end;
  replaceAll:=proc;
end;