public ActionResult SearchUser(string username)
        {
            UserModel um = new UserModel();
            List<String> results = um.Search(username);
            String html_result = "";

            foreach (String result in results)
            {
                html_result += "<div class=\"row search_user_result\">";
                html_result += "<div class=\"col-md-9\">";
                html_result += "<div class=\"input-group\">";
                html_result += "<span class=\"input-group-addon\">";
                html_result += "<input id=\""+ result + "\" type=\"checkbox\" aria-label=\"...\">";
                html_result += "</span>";
                html_result += "<input id=\"test1\" type=\"text\" disabled style=\"width: 400px\" value=\"" + result + "\" class=\"form-control\" aria-label=\"...\">";
                html_result += "</div>";
                html_result += "</div>";
                html_result += "</div>";
            }
            html_result += "<br />";
            html_result += "<div class=\"row search_user_result\">";
            html_result += "<div class=\"col-md-8 col-md-offset-1\">";
            html_result += "<button type=\"button\" id=\"khoataikhoan\" class=\"btn btn-warning btn-xulytk\">Khóa Tài Khoản</button>";
            html_result += "<button type=\"button\" id=\"xoataikhoan\" class=\"btn btn-danger btn-xulytk\">Xóa Tài Khoản</button>";
            html_result += "<button type=\"button\" class=\"btn btn-info btn-xulytk\">Hủy Bỏ</button>";
            html_result += " </div>";
            html_result += "</div>";

            return Content(html_result, "text/plain");
        }
 public ActionResult Search(string term)
 {
     UserModel um = new UserModel();
     return Json(um.Search(term), JsonRequestBehavior.AllowGet);
 }