c# 在datagridview修改添加資料

表student一定要設定主鍵，否則會出錯

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Data.SqlClient;

namespace database

{

    public partial class Form1 : Form

    {

       public DataSet myds=new DataSet();

      SqlDataAdapter myda = new SqlDataAdapter("select * from student", "server=LENOVO-1389D547;database=master;uid=sa;pwd=8233");

        public Form1()

        {

            InitializeComponent();

            myda.Fill(myds, "stu");

            dataGridView1.DataSource = myds.Tables["stu"];

        }

        private void btn1_Click(object sender, EventArgs e)

        {

            DataTable dtshow = (DataTable)dataGridView1.DataSource;

            SqlCommandBuilder builder = new SqlCommandBuilder(myda);

            this.myda.Update(dtshow);

            MessageBox.Show("修改成功");

        }

    }

}