To Edit the DataGridview and also save it in a database table using c#

Question

I use MYSQL Server as my project backend.I have a DataGridView that gets filled with data from the database. when i make changes in the DataGridView cells and i click a saveButton the data need to change in DataGridView and also in database table.

here my coding:

using MySql.Data.MySqlClient;

using System;

using System.Data;

using System.IO;

using System.Windows.Forms;


namespace datagridview

{

public partial class Form1 : Form

{

DataTable datatab;

 MySqlDataAdapter mydtadp;

    MySqlCommandBuilder cmbl;

String MyConnection = "SERVER=*****;" +

            "DATABASE=****;" +

            "UID=root;" +

            "PASSWORD=pws";

public Form1()

    {

        InitializeComponent();

    }

 private void Form1_Load(object sender, EventArgs e)

    {

 MySqlConnection MyConn = new MySqlConnection(MyConnection);

        MyConn.Open();

        MySqlCommand comand = new MySqlCommand("select * from aster_scripts;", MyConn);

        datatab = new DataTable();

        mydtadp = new MySqlDataAdapter(comand);

        mydtadp.Fill(datatab);

        dataGridView1.DataSource = datatab;

        MyConn.Close();

    }

 private void BtnSave_Click(object sender, EventArgs e)

    {

        DataSet ds = new DataSet();

        cmbl = new MySqlCommandBuilder(mydtadp);

        mydtadp.Update(datatab);

        MessageBox.Show("SAVED");

}

}

}

i had a error like this (Additional information: Dynamic SQL generation for the UpdateCommand is not supported against a SelectCommand that does not return any key column information.) in line mydtadp.Update(datatab); How can this be done?

Answer 1

Please notice the module-level variables. And reference this MSDN piece Here if need be.

schema

create table aster_scripts
(   id int auto_increment primary key,
    i int not null,
    sThing varchar(30) not null
);

insert aster_scripts (i,sThing) values (8,'frog'),(11,'cat');

c#

using System;
using System.Data;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
using System.IO;

namespace WindowsFormsApplication1
{
    public partial class Form2 : Form
    {
        private MySqlDataAdapter mydtadp = new MySqlDataAdapter();
        private BindingSource bindingSource1 = new BindingSource();

        MySqlCommandBuilder cmbl;
        String MyConnection = "SERVER=hostname;" +
                    "DATABASE=dbname;" +
                    "UID=dbuser;" +
                    "PASSWORD=fffff";

        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            MySqlConnection MyConn = new MySqlConnection(MyConnection);
            MyConn.Open();

            mydtadp.SelectCommand=new MySqlCommand("select * from aster_scripts", MyConn);
            cmbl = new MySqlCommandBuilder(mydtadp);

            DataTable table = new DataTable();
            mydtadp.Fill(table);

            bindingSource1.DataSource = table;
            dataGridView1.DataSource = bindingSource1;
        }

        private void BtnSave_Click(object sender, EventArgs e)
        {
            mydtadp.Update((DataTable)bindingSource1.DataSource);

            MessageBox.Show("SAVED");
        }
    }
}

Chg data hit save Screen Shot

DB Entries

mysql> select * from aster_scripts;

+----+----------+--------+
| id | i        | sThing |
+----+----------+--------+
|  1 |        8 | frog   |
|  2 | 11333322 | cat    |
+----+----------+--------+