Unable to update database with DataGridView values

[sampalmer21]

Hi,

If I update a cell in the DataGridView control, I use the DataAdapter.Update(DataTable) method to update the database, but when I restart the application my changes are not in the database. Anyone have an idea? Here is my code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
 
namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        DataTable data;
        SqlDataAdapter adapter;
        SqlCommandBuilder builder;
        SqlConnection conn;
 
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
            this.FormClosing += new FormClosingEventHandler(Form1_FormClosing);
            conn = new SqlConnection(@"Server=.\SQLEXPRESS;Database=licensedb;Trusted_Connection=yes;");
            conn.Open();
            SqlCommand cmd = new SqlCommand(@"Select * FROM FeatureTable",conn);
            adapter = new SqlDataAdapter(cmd);
            data = new DataTable("FeatureTable");
            adapter.Fill(data);
            builder = new SqlCommandBuilder(adapter);
            BindingSource bSource = new BindingSource();
            bSource.DataSource = data;
            dataGridView1.DataSource = bSource;
            String text = builder.GetUpdateCommand().CommandText;
            dataGridView1.CellValueChanged += new DataGridViewCellEventHandler(dataGridView1_CellValueChanged);
        }
 
        void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
        {
            dataGridView1.EndEdit();
            adapter.Update(data);
        }
 
        void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            conn.Close();
        }
    }
}

[Plater]

Did you ever assign values to the InsertCommand and UpdateCommand of your data adapter? It doesn't look like you did.
You need those to write data back to database.

[sampalmer21]

But doesn't the SqlCommandBuilder automatically generate those commands. If I delete the SqlCommandBuilder object, then I get a NullReferenceException when I run adapter.Update(DataTable) which implies that it was supplying the commands for the adapter in the first place. So I'm still not sure about why the database doesn't update.

[sampalmer21]

Thank You Plater!

You were right in that I did not set the adapter.UpdateCommand property. This property has to be set to the builder.GetUpdateCommand() value, for example:

adapter.UpdateCommand = builder.GetUpdateCommand();