private void buttonTambah_Click(object sender, EventArgs e) { if (Kripto.IsNumber(textBoxNumber.Text) && Kripto.IsNumber(textBoxDivisor.Text)) { int num = Convert.ToInt32(textBoxNumber.Text); int div = Convert.ToInt32(textBoxDivisor.Text); if (div == 0) { MessageBox.Show("Divisor shouldn't equals 0"); } else if (num == 0) { MessageBox.Show("Number shouldn't equals 0"); } else if (num == div) { MessageBox.Show("Number shouldn't equals divisor"); } else { if (num > div) { num %= div; } if (num < 0) { num += (num / div - 1) * -div; } dataGridViewCRT.Rows.Add(new object[] { "X =", num, "mod", div }); textBoxNumber.Clear(); textBoxDivisor.Clear(); } } else { MessageBox.Show("Input Number"); } }