private void button4_Click(object sender, EventArgs e)
                {
                        connection.Open();
 			SqlCommand cmd = new SqlCommand("select MAX(payment_id) from Wages", connection);
 			Int32 NewID = (Int32)cmd.ExecuteScalar() + 1;
 			connection.Close();
			DataRow row = set.Tables["Wages"].NewRow();
                        row[0] = NewID;
                        row[1] = Convert.ToInt32(textBox1.Text);
                        row[2] = Convert.ToInt32(textBox2.Text);
                        row[3] = dateTimePicker1.Value;
                        row[4] = checkBox1.Checked;
                        set.Tables["Wages"].Rows.Add(row);
                        bind.ResumeBinding();
                }