public void GetLineFromCharIndexTest () { using (MaskedTextBox mtb = new MaskedTextBox ()) { for (int i = -100; i < 100; i++) { Assert.AreEqual (0, mtb.GetLineFromCharIndex (i), "#A" + i.ToString ()); } mtb.Text = "alñsdh gaph" + Environment.NewLine + "asldg"; for (int i = -100; i < 100; i++) { Assert.AreEqual (0, mtb.GetLineFromCharIndex (i), "#B" + i.ToString ()); } } }