Step 1: Place a gridview and bind it with the database, create columns in the gridview and convert that to template

Step 2: Place Footer template for each column that to be inserted and create the controls we need for inserting the row

step 3 : Here we are going to bind our dropdownlist , to do so create gridview rowcreated event and bind the dropdownlist

Step 4: Then create a onclick event for insert button , provide the CommandName="Insert" and write the code for inserting the records in database

Let's see the HTML Source code

<asp:GridView
ID="GridView1"
runat="server"
AutoGenerateColumns="False" DataKeyNames="Id" CellPadding="4" ForeColor="Black" GridLines="Vertical" ShowFooter="True" BackColor="White"
BorderColor="#DEDFDE" BorderStyle="Solid"
BorderWidth="2px" OnRowCreated="GridView1_RowCreated">
<RowStyle BackColor="#F7F7DE" />
<Columns>
<asp:TemplateField HeaderText="ID" InsertVisible="False" SortExpression="ID">
<EditItemTemplate>

<asp:Label ID="Label1" runat="server" Text='<%# Eval("ID") %>'></asp:Label>
</EditItemTemplate>
<ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("ID") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Name" SortExpression="Name">
<EditItemTemplate>

<asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("Name") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label2" runat="server" Text='<%# Bind("Name") %>'></asp:Label>
</ItemTemplate>
<FooterTemplate>
<asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
</FooterTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="isactive">
<EditItemTemplate>
<asp:TextBox ID="TextBox2" runat="server" Text='<%# Bind("isactive") %>'></asp:TextBox>

</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label3" runat="server" Text='<%# Bind("isactive") %>'></asp:Label> </ItemTemplate>
<FooterTemplate>
<asp:DropDownList ID="ddlIsActive" runat="server">
</asp:DropDownList>
</FooterTemplate> </asp:TemplateField>
<asp:TemplateField FooterStyle-HorizontalAlign="Center">
<FooterTemplate>
<asp:Button ID="btnInsert" runat="server" Text="Insert" CommandName="Insert" OnClick="InsertRows" />
</FooterTemplate>
</asp:TemplateField>
</Columns>

<FooterStyle BackColor="#CCCC99" />
<PagerStyle BackColor="#F7F7DE" ForeColor="Black" HorizontalAlign="Right" />
<EmptyDataTemplate>
No Record Found
</EmptyDataTemplate>
<SelectedRowStyle BackColor="#CE5D5A" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#6B696B" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="White" />

</asp:GridView>

Lets See the C# Code

using System;

using System.Collections.Generic;

using System.Collections;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Xml;

using System.Data;

using System.Data.SqlClient;

using System.Configuration;

public partial class _Default : System.Web.UI.Page {
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack) {
BindGrid(); //Binding the gridview on page load
}
}
/// <summary>
/// This method connect to Sql database, fetch data returns dataset
/// </summary>
/// <returns></returns>
public DataSet ReturnMenuDetails()
{
DataSet ds = new DataSet();
using (SqlConnection sqlconn = new SqlConnection(ConfigurationManager.ConnectionStrings ["SqlConnectionString"].ConnectionString.ToString()))
{
sqlconn.Open();
SqlDataAdapter sqldap = new
SqlDataAdapter("select ID , Name , isactive from detail", sqlconn); sqldap.Fill(ds);
}
return ds;
}
/// <summary>
/// This method return a datatable with empty row
/// </summary>
/// <returns></returns>
public DataTable ReturnEmptyDataTable()
{
DataTable dtMenu = new DataTable(); //declaringa datatable
DataColumn dcMenuID = new DataColumn("ID", typeof(System.Int32));

//creating a column in the same
//Name of column available in the sql server
dtMenu.Columns.Add(dcMenuID);// Adding column to the datatable

DataColumn dcMenuName = new
DataColumn("Name", typeof(System.String));
dtMenu.Columns.Add(dcMenuName);

DataColumn dcMenuActive = new
DataColumn("isactive", typeof(System.String));
dtMenu.Columns.Add(dcMenuActive);
DataRow datatRow = dtMenu.NewRow();

//Inserting a new row,datatable .newrow creates a blank row
dtMenu.Rows.Add(datatRow);//adding row to the datatable
return dtMenu;
}
/// <summary>
/// This method checks for no of rows returned from sql server and binds the
/// datasource with the gridview based on the resultset, if no rows returned are zero
/// from sql server then it will bind the datatable to the gridview to display the columns
/// when no record was returned
/// </summary>
public void BindGrid()
{
if (ReturnMenuDetails().Tables[0].Rows.Count > 0)
{
GridView1.DataSource = ReturnMenuDetails();
}
else {
GridView1.DataSource = ReturnEmptyDataTable();

}
GridView1.DataBind();
}
/// <summary>
/// This method will search the dropdownlist in the footer template of the gridview
/// and bind the dropdownlist for this example i have used arraylist
/// we can bind from database also
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void GridView1_RowCreated(object sender, GridViewRowEventArgs e)
{
//Checking whether the rended row is footer
if (e.Row.RowType == DataControlRowType.Footer)
{
ArrayList arraDropdown = new ArrayList();
arraDropdown.Add(new ListItem("Select", "-1"));
arraDropdown.Add(new ListItem("Yes", "Yes"));
arraDropdown.Add(new ListItem("No", "No"));
//searching for dropdownlist in the footer view of gridview
DropDownList ddl = (DropDownList)e.Row.Cells[0].FindControl("ddlIsActive");
//Binding the dropdownlist with arraylist
ddl.DataSource = arraDropdown;
ddl.DataBind();
}
}
/// <summary>
/// This method will be fired when ever the insert button is clicked
/// This method searches for the textbox and dropdownlist placed in
/// the footer template of gridview and passes the values to the
/// SQL query and binds the grid
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void InsertRows(object sender, EventArgs e)
{
TextBox txtName = (TextBox)GridView1.FooterRow.FindControl("TextBox4");
DropDownList ddlys = (DropDownList)GridView1.FooterRow.FindControl("ddlIsActive");
using (SqlConnection sqlconn = new SqlConnection(ConfigurationManager.ConnectionStrings ["SqlConnectionString"].ConnectionString.ToString()))
{
SqlCommand sqldap = new
SqlCommand("insert into switch_master(switch_Name,isactive,created_by) values ('" + txtName.Text + "','" + ddlys.SelectedItem.Text + "','Manoj')", sqlconn);
sqlconn.Open();
sqldap.ExecuteNonQuery();
}
BindGrid();
}
}

Thus we can insert new rows in the within gridview