DataGridView数据更新至数据库-整体更新

1.首先获取datagirdview的datatable

DataTable dt = dataGridView1.DataSource as DataTable;

public static bool UpdataSql(DataTable dt)
        {
            try
            {
                using (SqlConnection connection = new SqlConnection(PubVariant.ConnectionString))
                {
                    string strSql = "select * from CorrespondField";
                    using (SqlCommand cmd = new SqlCommand(strSql, connection))
                    {
                        using (SqlDataAdapter da = new SqlDataAdapter(cmd))
                        {                          
                            using (SqlCommandBuilder builder = new SqlCommandBuilder(da))
                            {
                                da.Update(dt);
                                return true;
                            }
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return false;
            }
        }

public class PubVariant
    {
        public static string connectionString = "server=localhost;database=Test;user id=sa;password=123456";
        public static string ConnectionString
        {
            get { return connectionString;  }
            set { connectionString = value; }
        }
    }