error on dynamic combobox asp.net when binding data - asp.net

Question

related to this post Fill ComboBox Dynamically in asp.net.. help required I follow the code from that post, but when I tried to binding data, I've got error
Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control.
<asp:TemplateField HeaderText="Step" SortExpression="ID"><InsertItemTemplate>
: <asp:DropDownList ID="DropDownList2" runat="server" DataSourceID="SqlDataSource3" AutoPostBack="true"
DataTextField="Name" DataValueField="code" SelectedValue='<%# Bind("ID") %>' AppendDataBoundItems="true"
Width="300px" Height="25px">
<asp:ListItem Value=" " Text="---Select---"></asp:ListItem>
</asp:DropDownList>
</InsertItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="KKL Step" SortExpression="ID">
<InsertItemTemplate>
: <asp:DropDownList ID="DropDownList6s" runat="server" DataSourceID="SqlDataSource5"
DataTextField="KKL_Name" DataValueField="ID" AppendDataBoundItems="true"
SelectedValue='<%# Bind("ID") %>' Width="300px" Height="25px">
<asp:ListItem Value="" Text="---Select---"></asp:ListItem>
</asp:DropDownList>
<asp:SqlDataSource ID="SqlDataSource5" runat="server"
ConnectionString="<%$ ConnectionStrings:Koneksi %>"
SelectCommand="SELECT * FROM [TBL_KKL] WHERE (code=#code)">
<SelectParameters>
<asp:controlParameter controlID="DropDownList2"
propertyname="SelectedValue" Name="code" Type="String" />
</SelectParameters>
</asp:SqlDataSource>
</InsertItemTemplate>
</asp:TemplateField>

Answer 1

Its better to bind values to dropdown lists using C# code. Its ease and clear.
So in the RowDataBound event of the gridview you can write a code similar to this according to your syntax.
protected void dtgItemDetails_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataTable dtDetails = GetDetailsFromDataBase();
DropDownList DropDownList2= (DropDownList)e.Row.FindControl("DropDownList2");
DropDownList2.DataTextField = "Name";
DropDownList2.DataValueField = "ID";
DropDownList2.DataSource = dtDetails ;
DropDownList2.DataBind();
}
}
This is a sample code and you should change it according to yours.
Instead of DB calls inside the RowDataBound method, you can have Sessions or ViewStates with already filled with your data.