my code is:

protected void WebDataGrid1_ItemCommand(object sender, Infragistics.Web.UI.GridControls.HandleCommandEventArgs e)
{
GridRecordItem item = WebDataGrid1.Behaviors.Activation.ActiveCell;
if (item == null)
return;

......

}

in aspx code, The grid control bound a column as follow:

<ig:TemplateDataField Key="Operation" Width="40px">
<ItemTemplate>
<center>
<asp:LinkButton ID="LinkButtonMapping" runat="server" Font-Underline="True" 
ForeColor="#0000CC" CommandName="update" >name1</asp:LinkButton>
</center>
</ItemTemplate>
<Header Text="Operate" />
</ig:TemplateDataField>

My question is:

The ActiveCell is null sometimes when I click link "update" in the grid. But sometimes ActiveCell is not null.  I do not know why.

The grid has 20000 datas and has Paging behavior.