DataTable修改后，如何更新数据库

DataTable中的数据可以修改多个后，同时更新到数据库，这样比较方便。下面是实现的代码： DataTable table = new DataTable();//初始化一个DataTable对象 string sqlConnectionString = Data Source=ComputerName-PC;Initial Catalog=charge_sys;User ID=sa;

       DataTable中的数据可以修改多个后，同时更新到数据库，这样比较方便。下面是实现的代码：

<span>            DataTable table = new DataTable();//初始化一个DataTable对象
            
            string sqlConnectionString = "Data Source=ComputerName-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;";
            SqlConnection sqlConnection = new SqlConnection(sqlConnectionString);//连接数据库
            
            SqlCommand sqlCommand = new SqlCommand("select * from testB", sqlConnection);
            
            SqlDataAdapter sqlAdap = new SqlDataAdapter(sqlCommand);
            SqlCommandBuilder sqlBuilder = new SqlCommandBuilder(sqlAdap);//这句挺重要的，好像是批量更新的时候用
            
            //DataSet dtst = new DataSet();      用dataSet也可以完成，下面有对应实现的代码

            sqlConnection.Open();
            sqlAdap.Fill(table);
       
            //table = dtst.Tables["testB"];

            DataRow dr = table.Rows[0];//第一行
            
            //dr.BeginEdit();
            //dr.EndEdit();     貌似这两句主要是数据绑定到控件的时候才用

            for (int i = 0; i </span>

       下面是DataTable与dataGridView   控件绑定，当dataGridView中的数据改变时，更新数据库的代码：

             DataTable和dataGridView控件绑定代码：

<span>private void Form1_Load(object sender, EventArgs e)
        {
            string sqlConnectionString = "Data Source=ComputerName-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;";
            SqlConnection sqlConnection = new SqlConnection(sqlConnectionString);//初始化sqlconnection

            DataTable table = new DataTable();
            SqlDataAdapter sqlAdap = new SqlDataAdapter("select * from testB ", sqlConnection);

            sqlConnection.Open();
            sqlAdap.Fill(table);
            sqlConnection.Close();

            //将testB表中的数据显示在dataGridView中
            this.dataGridView1.DataSource = table;

        }</span>

           实现将dataGridView中的改动更新到数据库代码：

<span>private void butUpdate_Click(object sender, EventArgs e)
        {
            DataTable table = new DataTable();
            table = (DataTable)this.dataGridView1.DataSource;

            string sqlConnectionString = "Data Source=WangHaitao-PC;Initial Catalog=charge_sys;User ID=sa;PWD=123456;";
            SqlConnection sqlConnection = new SqlConnection(sqlConnectionString);
            
            SqlCommand sqlCommand = new SqlCommand("select * from testB", sqlConnection);
            
            SqlDataAdapter sqlAdap = new SqlDataAdapter(sqlCommand);
            SqlCommandBuilder sqlBuilder = new SqlCommandBuilder(sqlAdap);//必须有

            sqlConnection.Open();
            sqlAdap.Fill(table);

            //testB表中必须存在主键，否则无法更新
            sqlAdap.Update(table);

            sqlConnection.Close();
            MessageBox.Show("aa");

        }</span>