Fetching Data Key in Row Command

protected void gvArtist_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        int intUserGridID=0;
        if (e.CommandName == AdminConstantKeys.ViewGigsCommandName)
        {
            int intHeaderMasterID = -1;
            GridViewRow grArtist = ((Control)
                (e.CommandSource)).NamingContainer as GridViewRow;

            //Check if command raised by DataRow or not
            if (grArtist.RowIndex != -1)
            {
                intUserGridID =
                    int.Parse(gvArtist.DataKeys[grArtist.RowIndex].Values
                    [AdminConstantKeys.UserID].ToString());


                Session[AdminConstantKeys.GigsArtistName] = e.CommandArgument.ToString();
                Response.Redirect("../ArtistManagement/ViewGigs.aspx?Id=" + intUserGridID);
            }
        }
    }