Gridview insert update delete

Gridview ---->Edit Templates------>Choose ItemTemplate and then drag and drop Link button----> go tt property and change the name as Edit or Delete---->After that Click the the LinkButton Task----> EditDataBindings---->Command Argument ---->((GridViewRow) Container).RowIndex----> And then Click ok

 protected void Button1_Click(object sender, EventArgs e)
        {


            if (Button1.Text == "Insert")
            {
                SqlCommand cmd = new SqlCommand("spEmpp", con);

                con.Open();
                cmd.CommandType = CommandType.StoredProcedure; 
                HiddenField1.Value = "insert";
                cmd.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();
                cmd.Parameters.AddWithValue("@id", 0);
                cmd.Parameters.AddWithValue("@FirstName", txt_Fname.Text.ToString());       
                cmd.Parameters.AddWithValue("@Mname ", txt_mname.Text.ToString());    
                cmd.Parameters.AddWithValue("@LastName ", txt_lname.Text.ToString());      
                cmd.ExecuteNonQuery();
                con.Close();
                Lbl_Result.Visible = true;
                Lbl_Result.Text = "Records are Submitted Successfully";
                viewdata();

            }
            else
            {
                SqlCommand cmd = new SqlCommand("spEmpp", con);
                con.Open();
                cmd.CommandType = CommandType.StoredProcedure;
                HiddenField1.Value = "update";
                cmd.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();
                cmd.Parameters.AddWithValue("@id", Session["id"].ToString());
                //cmd.Parameters.AddWithValue("@id",HiddenField2.Value);
                cmd.Parameters.AddWithValue("@FirstName", txt_Fname.Text.ToString());
                cmd.Parameters.AddWithValue("@Mname ", txt_mname.Text.ToString());
                cmd.Parameters.AddWithValue("@LastName ", txt_lname.Text.ToString());
                cmd.ExecuteNonQuery();
                con.Close();
                Lbl_Result.Visible = true;
                Lbl_Result.Text = "Records are Updated Successfully";
                viewdata();

            }

            Clear();
        }
private void viewdata()
        {
            con.Open();
            cmd = new SqlCommand("select * from emp", con);
            DataSet ds = new DataSet();
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            da.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
        }
  protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
        {

            if (e.CommandName == "Edit")
            {
                int index = Convert.ToInt32(e.CommandArgument);
               // HiddenField2.Value = GridView1.DataKeys[index].Value.ToString();
                Session["id"] = GridView1.DataKeys[index].Value.ToString(); 
                txt_Fname.Text = GridView1.Rows[index].Cells[1].Text.Trim();
                txt_lname.Text = GridView1.Rows[index].Cells[3].Text.Trim();
                txt_mname.Text = GridView1.Rows[index].Cells[2].Text.Trim(); 
                Button1.Text = "Update";
            }
            else if (e.CommandName == "Delete")
            {
                 int index = Convert.ToInt32(e.CommandArgument);
                Session["id"]= GridView1.DataKeys[index].Value.ToString();
                txt_Fname.Text = GridView1.Rows[index].Cells[1].Text.Trim();
                txt_lname.Text = GridView1.Rows[index].Cells[3].Text.Trim();
                txt_mname.Text = GridView1.Rows[index].Cells[2].Text.Trim();
                SqlCommand cmd = new SqlCommand("spEmpp", con);

                con.Open();

               
                cmd.CommandType = CommandType.StoredProcedure; 
                HiddenField1.Value = "delete";
                cmd.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();
                cmd.Parameters.AddWithValue("@id", Session["id"].ToString());
                //cmd.Parameters.AddWithValue("@id", HiddenField2.Value);
                cmd.Parameters.AddWithValue("@FirstName", txt_Fname.Text.ToString());
                cmd.Parameters.AddWithValue("@Mname ", txt_mname.Text.ToString());
                cmd.Parameters.AddWithValue("@LastName ", txt_lname.Text.ToString());
              
                cmd.ExecuteNonQuery();
                con.Close();

                Lbl_Result.Visible = true;
                Lbl_Result.Text = "Records are deleted Successfully";
                Clear();
                viewdata();
                Button1.Text = "Insert";

              




            }

        }

        protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
        {

        }

        protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
        {

        }

        public void Clear()
        {
            txt_Fname.Text = "";
            txt_lname.Text = "";
            txt_mname.Text = "";
        }


    }
}
<tr>
                    <asp:GridView ID="GridView1" runat="server" DataKeyNames="id"
                    AutoGenerateColumns="False" onrowediting="GridView1_RowEditing"
                    onrowcommand="GridView1_RowCommand" onrowdeleting="GridView1_RowDeleting">
                        <Columns>
                            <asp:BoundField DataField="id" HeaderText="id" ReadOnly="True"
                                ShowHeader="False" />
                            <asp:BoundField DataField="FirstName" ReadOnly="true" HeaderText="FirstName" />
                            <asp:BoundField DataField="MName"   HeaderText=" MName" ReadOnly="True"
                                SortExpression="MName" />
                            <asp:BoundField DataField="LastName" HeaderText="LastName" ReadOnly="True"
                                SortExpression="LastName" />
                            <asp:TemplateField>
                                <ItemTemplate>
                                    <asp:LinkButton ID="LinkButton1" runat="server" CommandName="Edit" 
                                        CommandArgument="<%# ((GridViewRow) Container).RowIndex %>">Edit</asp:LinkButton>
                                    &nbsp;
                                    <asp:LinkButton ID="LinkButton2" runat="server"  CommandName="Delete"
                                        CommandArgument="<%# ((GridViewRow) Container).RowIndex %>">Delete</asp:LinkButton>
                                </ItemTemplate>
                            </asp:TemplateField>
                        </Columns>
                    </asp:GridView>
                </tr>
                <tr>
                    <asp:HiddenField ID="HiddenField1" runat="server" />
                     <asp:HiddenField ID="HiddenField2" runat="server" />
                    <td>
                        &nbsp;&nbsp;&nbsp;
                        <br />
                        <asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Insert" />
                    </td>
                </tr>
                <input id="Reset1" type="reset" value="reset" /><div align="center">
                  

                </div>
            </div>
                <tr>
                    <td>
                        <asp:Label ID="Lbl_Result" runat="server" Text=""></asp:Label>
                    </td>
                    <td>
                        &nbsp;</td>
                </tr>