Hi Waghmare,

Please refer below sample.

Database

I have made use of the following table Customers with the schema as follows.

I have already inserted few records in the table.

You can download the database table SQL by clicking the download link below.

Download SQL file

Namespaces

C#

using System.Data;
using System.Data.SqlClient;

VB.Net

Imports System.Data
Imports System.Data.SqlClient

Code

C#

public Form1()
{
    InitializeComponent();
    string ConnectionString = @"Data Source=.;Initial Catalog=Test;User id = sa;password=pass@123";
    using (SqlConnection con = new SqlConnection(ConnectionString))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CustomerId, Name, Country FROM Customers", con))
        {
            cmd.CommandType = CommandType.Text;
            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                using (DataTable dt = new DataTable())
                {
                    sda.Fill(dt);
                    BindGrid(dt);
                }
            }
        }
    }
}

private void BindGrid(DataTable dt)
{
    //Hide the last blank line.
    gvCustomers.AllowUserToAddRows = false;

    //Clear Columns.
    gvCustomers.Columns.Clear();

    //Add Columns.
    DataGridViewColumn customerId = new DataGridViewTextBoxColumn();
    customerId.Name = "CustomerId";
    customerId.HeaderText = "CustomerId";
    customerId.DataPropertyName = "CustomerId";
    customerId.Width = 100;
    gvCustomers.Columns.Insert(0, customerId);

    DataGridViewColumn name = new DataGridViewTextBoxColumn();
    name.HeaderText = "Name";
    name.Name = "Name";
    name.DataPropertyName = "Name";
    name.Width = 100;
    gvCustomers.Columns.Insert(1, name);

    DataGridViewColumn country = new DataGridViewTextBoxColumn();
    country.Name = "Country";
    country.HeaderText = "Country";
    country.DataPropertyName = "Country";
    country.Width = 100;
    gvCustomers.Columns.Insert(2, country);

    //Bind the DataGridView.
    gvCustomers.DataSource = null;
    gvCustomers.DataSource = dt;

    //Add the Button Column.
    DataGridViewButtonColumn buttonColumn = new DataGridViewButtonColumn();
    buttonColumn.HeaderText = "Modify";
    buttonColumn.Width = 60;
    buttonColumn.Name = "buttonColumn";
    buttonColumn.Text = "Edit";
    buttonColumn.UseColumnTextForButtonValue = true;
    gvCustomers.Columns.Insert(0, buttonColumn);
}

protected void OnSave(object sender, EventArgs e)
{
    DataTable dt = gvCustomers.DataSource as DataTable;

    BindGrid(dt);
}

VB.Net

Public Sub New()
    InitializeComponent()
    Dim ConnectionString As String = "Data Source=.;Initial Catalog=Test;User id = sa;password=pass@123"
    Using con As SqlConnection = New SqlConnection(ConnectionString)
        Using cmd As SqlCommand = New SqlCommand("SELECT CustomerId, Name, Country FROM Customers", con)
            cmd.CommandType = CommandType.Text
            Using sda As SqlDataAdapter = New SqlDataAdapter(cmd)
                Using dt As DataTable = New DataTable()
                    sda.Fill(dt)
                    BindGrid(dt)
                End Using
            End Using
        End Using
    End Using
End Sub

Private Sub BindGrid(ByVal dt As DataTable)
    gvCustomers.AllowUserToAddRows = False
    gvCustomers.Columns.Clear()
    Dim customerId As DataGridViewColumn = New DataGridViewTextBoxColumn()
    customerId.Name = "CustomerId"
    customerId.HeaderText = "CustomerId"
    customerId.DataPropertyName = "CustomerId"
    customerId.Width = 100
    gvCustomers.Columns.Insert(0, customerId)
    Dim name As DataGridViewColumn = New DataGridViewTextBoxColumn()
    name.HeaderText = "Name"
    name.Name = "Name"
    name.DataPropertyName = "Name"
    name.Width = 100
    gvCustomers.Columns.Insert(1, name)
    Dim country As DataGridViewColumn = New DataGridViewTextBoxColumn()
    country.Name = "Country"
    country.HeaderText = "Country"
    country.DataPropertyName = "Country"
    country.Width = 100
    gvCustomers.Columns.Insert(2, country)
    gvCustomers.DataSource = Nothing
    gvCustomers.DataSource = dt
    Dim buttonColumn As DataGridViewButtonColumn = New DataGridViewButtonColumn()
    buttonColumn.HeaderText = "Modify"
    buttonColumn.Width = 60
    buttonColumn.Name = "buttonColumn"
    buttonColumn.Text = "Edit"
    buttonColumn.UseColumnTextForButtonValue = True
    gvCustomers.Columns.Insert(0, buttonColumn)
End Sub

Protected Sub OnSave(ByVal sender As Object, ByVal e As EventArgs)
    Dim dt As DataTable = TryCast(gvCustomers.DataSource, DataTable)
    BindGrid(dt)
End Sub

Screenshot