SqlClass.cn.Close();//cn为sqlconnection实例
                dataGridView1.ReadOnly = false;
                dataGridView1.CurrentRow.Cells[0].Value = textBox1.Text;
                dataGridView1.CurrentRow.Cells[1].Value = textBox2.Text;
                dataGridView1.CurrentRow.Cells[3].Value = Int32.Parse(textBox3.Text);
                if (radioButton1.Checked == true)
                    dataGridView1.CurrentRow.Cells[2].Value = "男";
                if (radioButton2.Checked == true)
                    dataGridView1.CurrentRow.Cells[2].Value = "女";
                DataTable tb = dataGridView1.DataSource as DataTable;
                string sql = "select * from employee";
                SqlDataAdapter sda = new SqlDataAdapter(sql, SqlClass.cn);
                SqlCommandBuilder scb = new SqlCommandBuilder(sda);
                sda.Update(tb);
                MessageBox.Show("修改成功");
                dataGridView1.ReadOnly = true;
                SqlClass.cn.Open();
//以上更新方法在直接修改datagridview内数据可用，想更改成利用文本框数据来更改数据库数据时datagridview会更改，但不会更改数据库内数据，且没有异常可catch