Dev Express Gridview saving the layout in the session variable example. This persists the layout during a user's session.
OnClientLayout="gvCustomers_ClientLayout"
protected void gvCustomers_ClientLayout(object sender, DevExpress.Web.ASPxClasses.ASPxClientLayoutArgs e) {
if (e.LayoutMode == DevExpress.Web.ASPxClasses.ClientLayoutMode.Saving)
Session["gridLayout"] = e.LayoutData;
else
if (Session["gridLayout"]!=null)
e.LayoutData = Session["gridLayout"].ToString();
}