在模型中使用远程安全验证

        [HttpGet] //必须get,必须json
        public ActionResult CheckItemCodeExists(string ItemCode)  //注意参数名称与前端的元素ID（属性名同名）
        {
            string[] itemCodes = { "bmw-x5", "audi-q7"};
            bool isValid = string.IsNullOrEmpty(itemCodes.FirstOrDefault(x => x == ItemCode));
            return Json(isValid, JsonRequestBehavior.AllowGet); //必须get,必须json
        }

    public class ItemModel
    {
        [DisplayName("物料代码")]
        [Required(ErrorMessage = "[物料代码]不能为空")]
        [Remote("CheckItemCodeExists", "Test", ErrorMessage = "[物料代码]已存在")]
        public string ItemCode { get; set; }
    }

@model  MvcApplication3.Models.ItemModel

@section header1 { 
    <script src="@Url.Content("~/Scripts/jquery-1.8.2.min.js")" type="text/javascript"></script>
    <script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
    <script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>
}

@{
    ViewBag.Title = "Index";
}

<h2>添加用户</h2>
<fieldset>
    <legend>添加用户</legend>
    <div>
        @using(Html.BeginForm("index","Test")){
        <p>
            @Html.ValidationSummary(true)

            @Html.LabelFor(m=>m.ItemCode)：
            @Html.TextBoxFor(m=>m.ItemCode)
            @Html.ValidationMessageFor(m=>m.ItemCode)
        </p>
        <p>
            <input type="submit" value="提 交" />
        </p>
        }
    </div>
</fieldset>