Display selected GridView Row details in DetailsView in ASP.Net

Please refer this code

HTML

<asp:GridView ID="GridView1" HeaderStyle-BackColor="#3AC0F2" HeaderStyle-ForeColor="White"
    runat="server" OnSelectedIndexChanged="GridView1_OnSelectedIndexChanged" AutoGenerateSelectButton="true"
    AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="Id" HeaderText="Id" ItemStyle-Width="30" />
        <asp:BoundField DataField="Name" HeaderText="Name" ItemStyle-Width="150" />
        <asp:BoundField DataField="Country" HeaderText="Country" ItemStyle-Width="150" />
    </Columns>
</asp:GridView>
<hr />
<asp:DetailsView ID="SelectedUser" runat="server" AutoGenerateRows="false">
    <Fields>
        <asp:TemplateField HeaderText="Id">
            <ItemTemplate>
                <asp:TextBox ID="txtId" runat="server" Text='<%# Eval("Id") %>' />
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Name">
            <ItemTemplate>
                <asp:TextBox ID="txtName" runat="server" Text='<%# Eval("Name") %>' />
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Country">
            <ItemTemplate>
                <asp:TextBox ID="txtCountry" runat="server" Text='<%# Eval("Country") %>' />
            </ItemTemplate>
        </asp:TemplateField>
    </Fields>
</asp:DetailsView>

Namespace

using System.Data;

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(int)),
                        new DataColumn("Name", typeof(string)),
                        new DataColumn("Country",typeof(string)) });
        dt.Rows.Add(1, "John Hammond", "United States");
        dt.Rows.Add(2, "Mudassar Khan", "India");
        dt.Rows.Add(3, "Suzanne Mathews", "France");
        dt.Rows.Add(4, "Robert Schidner", "Russia");
        GridView1.DataSource = dt;
        GridView1.DataBind();
    }

}

protected void GridView1_OnSelectedIndexChanged(object sender, EventArgs e)
{
    GridViewRow row = this.GridView1.SelectedRow;
        
    DataTable dt = new DataTable();
    dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(string)),
                        new DataColumn("Name", typeof(string)),
                        new DataColumn("Country",typeof(string)) });
    dt.Rows.Add(row.Cells[1].Text, row.Cells[2].Text, row.Cells[3].Text);
    SelectedUser.DataSource = dt;
    SelectedUser.DataBind();
}

Screenshot