How to find TextBox value in gridview using c# .net?

In client side(Default.aspx)

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" DataKeyNames="Id" OnRowCommand="GridView1_RowCommand" BorderWidth="1px" CellPadding="3" CellSpacing="2">

                <Columns>

                    <asp:TemplateField>

                        <ItemTemplate>

                            <asp:LinkButton ID="lnkInsert" runat="server" CommandArgument='<%# Eval("Id") %>' CommandName="lnkInsert" Text="Insert" ForeColor="#BC4510" />

 

                            <asp:TextBox ID="txtName" runat="server" />

                        </ItemTemplate>

                    </asp:TemplateField>

                </Columns>

 

            </asp:GridView>

In Code behind(Default.aspx.cs)

protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)

        {

            if (e.CommandName == "lnkInsert")

            {

                int RowIndex = ((GridViewRow)((LinkButton)e.CommandSource).NamingContainer).RowIndex;

                string name = ((TextBox)GridView1.Rows[RowIndex].FindControl("txtName")).Text;

            }

        }