Modelstate的数据验证

  
    

   
     
   
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     <
   
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     input type
   
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     <
   
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     password
   
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利用ModelState来判断

 [AcceptVerbs("POST")]

        public ActionResult Index(Models.UserModel model)

        {

            if (model != null)

            {

                if (string.IsNullOrEmpty(model.Name))

                {

                    ModelState.AddModelError("Name", "名称不能为空");

                }

                else if (model.Name.Length > 20)

                {

                    ModelState.AddModelError("Name", "名称长度不能大于20");

                }

            }

            if (ModelState.IsValid)

            {

                //如果没错误

            }

            else

            {

                //如果有错误

               

            }

            return View(model);





            

        }

简单的验证就好了