Loading when Paging clicks in GRIDVIEW asp.net

Hi,
A event called PageIndexChanging is there with gridview. You can use that for the paging. Here is a sample code:

protected void gvArticals_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
    try
    {
       gvArticals.DataSource = dtArticle;//dtArticle is your datasource
       gvArticals.PageIndex = e.NewPageIndex;
       gvArticals.DataBind();
    }
    catch (Exception ex)
    {
       //Handle the exception here
    }
}

Yes, now you want a loading image for gridview while paging. Put your gridview inside asp:UpdatePanel and asp:UpdateProgress. Example:

<asp:scriptmanager id="ScriptManager1" runat="server" xmlns:asp="#unknown">
</asp:scriptmanager>
<asp:updateprogress id="updProgress" xmlns:asp="#unknown">
    AssociatedUpdatePanelID="UpdatePanel1"
    runat="server">
    <progresstemplate>            
        <img alt="progress" src="images/progress.gif" />
           Processing...            
    </progresstemplate>
</asp:updateprogress>

<asp:updatepanel id="UpdatePanel1" runat="server" xmlns:asp="#unknown">
    <contenttemplate>
         <asp:gridview id="gvArticals" runat="server"></asp:gridview>
    </contenttemplate>
</asp:updatepanel>   

Note:One instance of ScriptManager is require to run the ajax controls.
For positioning the image in the gridview's center refer the following link:
http://www.w3schools.com/cssref/pr_class_position.asp[^]
All the best.
--Amit