Hi ,
you can use Row_command Event of Grid view for get GridView Row index.
at Aspx page Side UI.
<asp:gridview id="GridView1" runat="server" onrowcommand="GridView1_RowCommand" xmlns:asp="#unknown">
<columns>
<asp:templatefield headertext="Select">
<itemtemplate>
<asp:button id="btnSelect">CommandArgument="<%# ((GridViewRow) Container).RowIndex %>" CommandName="Select" />
</asp:button></itemtemplate>
</asp:templatefield>
</columns>
</asp:gridview>
in .cs file
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Select")
{
int intRowid = Convert.ToInt16(e.CommandArgument);
GridViewRow GrdRow = GridView1.Rows[intRowid];
}
}