procedure TForm1.Button1Click(Sender: TObject);
var
  i, iCount, iLength, iTag: Integer;
  sFind, sTmp: String;
begin
  sFind:= Edit1.Text;
  iCount:= 0;      for i:=0 to RichEdit1.Lines.Count -1 do
  begin
    iLength:= 0;
    sTmp:= RichEdit1.Lines.Strings[i];
    while Pos(sFind, sTmp) > 0 do
    begin
      iTag:= Pos(sFind, sTmp);
      RichEdit1.SelStart:= iTag-1 iCount iLength;
      RichEdit1.SelLength:= Length(sFind);
      RichEdit1.SelAttributes.Color:= clRed;          iLength:= iTag   Length(sFind)  iLength -1;          sTmp:= Copy(sTmp, iTag Length(sFind), MAXINT);
    end;
    iCount:= iCount   Length(RichEdit1.Lines.Strings[i])   2;
  end;    end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  DrawColor(RichEdit1,edit1.Text ,0);
end;    procedure TForm1.DrawColor(RichEdit :TRichEdit ;sSel :string ; iForm :integer) ;
var iGet :integer;
begin
  iGet := RichEdit.FindText(sSel,iForm,maxint,[stMatchCase]);
  if iGet >0 then
  begin
    RichEdit.SelStart := iGet ;
    RichEdit.SelLength := Length(sSel);
    RichEdit.SelAttributes.Color:= clRed;
    DrawColor(RichEdit,sSel ,iGet 1);
  end;
end;