How to force RadGrid to postback when inner grid expand

Question

I have a hierarchical RadGrid and I wrote the following code that works when I select a row because I set EnablePostBackOnRowClick="true" but I want to when I expand the subgrid, it fill but now I had to select the row to bind detail grid.

protected void RadGrid1_DetailTableDataBind(object source, Telerik.Web.UI.GridDetailTableDataBindEventArgs e)
{
    //e.DetailTableView.Items[e.DetailTableView.ParentItem.ItemIndex]["ID_"].Text
    try
    {
        if (x != "0")
        {
            x = RadGrid1.Items[RadGrid1.SelectedIndexes[0]]["ID_"].Text.ToString();
        }
        GridDataItem dataItem = (GridDataItem)e.DetailTableView.ParentItem;
        // Label2.Text = e.DetailTableView.Items[0]["ControlName"].Text.ToString();

        e.DetailTableView.DataSource = GetDataTable("[Prg].[S_ControlList_Select]", x);
    }
}

Answer 1

In order to have your page fire a postback when you expand the subgrid, just set the following:

In your RadGrid's definition, add the OnItemCommand setting and the ClientSettings section:

<telerik:RadGrid ID="RadGrid1" OnItemCommand="RadGrid1_ItemCommand"
    <ClientSettings AllowExpandCollapse="true">

In the code behind, handle the postback:

protected void RadGrid1_ItemCommand(object sender, GridCommandEventArgs e)
{
    switch (e.CommandName)
    {
        case "ExpandCollapse":
            // Do something...
            break;
    }
}