Dynamically Creating Data-table and Binding To Grid-view

Question

Dynamically Creating DataTable and Binding To GridView i want store all gridview data in database at time.

 

Source aspx page

<form id="form1" runat="server">
<div>
<asp:TextBox ID="txt_id" runat="server" placeholder="ID"></asp:TextBox><br />
<asp:TextBox ID="txt_name" runat="server" placeholder="Name"></asp:TextBox><br />
<asp:Button ID="Button1" runat="server" Text="Button" onclick="btn_1_Click"/>
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
<asp:Button ID="Button2" runat="server" Text="Button" OnClick="btn_2_Click"/>
</div>
</form>

CS file

protected void btn_1_Click(object sender, EventArgs e)
{
GridView1.Visible = true;
createnewrow();
}
public void createnewrow()
{
DataTable mytable = new DataTable();
if (ViewState["Row"] != null)
{
mytable = (DataTable)ViewState["Row"];
DataRow dr = null;
if (mytable.Rows.Count > 0)
{
dr = mytable.NewRow();
dr["Id"] = txt_id.Text;
dr["Name"] = txt_name.Text;
mytable.Rows.Add(dr);
ViewState["Row"] = mytable;
GridView1.DataSource = ViewState["Row"];
GridView1.DataBind();
}
}
else
{
mytable.Columns.Add("Id", typeof(int));
mytable.Columns.Add(new DataColumn("Name", typeof(string)));
DataRow dr1 = mytable.NewRow();
dr1 = mytable.NewRow();
dr1["Id"] = txt_id.Text;
dr1["Name"] = txt_name.Text;
mytable.Rows.Add(dr1);
ViewState["Row"] = mytable;
GridView1.DataSource = ViewState["Row"];
GridView1.DataBind();
}
}
// this is my save button
protected void btn_2_Click(object sender, EventArgs e)
{
con.Open();
SqlCommand com = new SqlCommand("tbl_adda", con);
com.CommandType = CommandType.StoredProcedure;
com.Parameters.AddWithValue("@Id", Convert.ToInt32(txt_id.Text));
com.Parameters.AddWithValue("@Name", txt_name.Text.ToString());
com.ExecuteNonQuery();
con.Close();
}

please help me