This example demonstrates how to restore state of grid detail rows if the user leaves a page and then returns back.
To accomplish this task, perform the following:
1) Disable the page's cache as it is described in the Why controls do not work properly when clicking browser Back / Forward buttons article.
2) Handle the grid's DetailRowExpandedChanged event to save the expanded state. The session is used in this example.
[C#]</para><para>settings.DetailRowExpandedChanged=(s,e)=>{</para><para>if(e.Expanded)</para><para>rows.Add(e.VisibleIndex);</para><para>else</para><para>rows.Remove(e.VisibleIndex);</para><para>};</para><para>
3) Handle the grid's client-side Init event to send a get request to the server to see if it is necessary to expand rows.
[JavaScript]</para><para>function OnInit(s, e){</para><para> $.ajax({</para><para> type: "GET",</para><para> dataType: "text",</para><para> url: '@Url.Action("ShouldSendCallback", "Home")',</para><para> success: function(sendCallback){</para><para> if(sendCallback)</para><para> GridView.PerformCallback();</para><para> }</para><para> });</para><para>}</para><para>
4) Handle the grid's BeforeGetCallbackResult event to expand detail rows during the callback if necessary.
[C#]</para><para>settings.BeforeGetCallbackResult=(s,e)=>{</para><para>vargrid=sasMVCxGridView;</para><para>if(rows.Count!=grid.DetailRows.VisibleCount){</para><para>foreach(intiteminrows){</para><para>grid.DetailRows.ExpandRow(item);</para><para>}</para><para>grid.PageIndex=Convert.ToInt32(Session["curPage"]);</para><para>}</para><para>Session["curPage"]=grid.PageIndex;</para><para>};</para><para>
