[lmikle]

Ну, например, так:

Код:

var
  L : TStringList;
  I, C : Integer;
begin
  C := 0;
  L := TStringList.Create;
  Try
    L.LoadFromFile('filename.txt');
    For I := 0 To L.Count-1 Do
      If Pos('Test1',L[i]) = 1 Then Inc(C);
  Finally
    L.Free;
  End;
  ShowMessage(IntToStr(C));
end;