In MVC, Model is not only a data transmitter, but also an mvcmodel.

In MVC, Model is not only a data transmitter, but also an mvcmodel.

When using a Model, many people use it the same way as when writing a three-tier architecture, and use the Model as the data transmitter.

For example, common writing

        public int Id { get; set; }        public int RoleId { get; set; }        public string Name { get; set; }        public string Password { get; set; }                public string NickName { get; set; }               public string Avatar { get; set; }        public string Email { get; set; }        public string Phone { get; set; }        public string Qq { get; set; }        public DateTime AddTime { get; set; }                public DateTime LastLoginTime { get; set; }        public string LastLoginIp { get; set; }        public bool IsLock { get; set; }                public bool IsSuperUser { get; set; }

This writing method is the most common, and I have seen many code generators generate this way. Many people regard the model as a data transmitter and a temporary data zone.

In fact, the Model can also be used to verify data. Reference: using System. ComponentModel. DataAnnotations; space

[Display (Name = "ID")] public int Id {get; set;} [Required (ErrorMessage = "role ID cannot be blank")] [Display (Name = "role ID")] public int RoleId {get; set;} [Required (ErrorMessage = "account Name cannot be blank")] [Display (Name = "account Name")] public string Name {get; set;} [Required (ErrorMessage = "password cannot be blank")] [Display (Name = "Password")] public string Password {get; set;} [Display (Name = "NickName")] public string NickName {get; set ;} [Display (Name = "Avatar")] [DataType (DataType. text)] public string Avatar {get; set;} [Display (Name = "Email")] public string Email {get; set ;} [Display (Name = "Mobile Phone")] public string Phone {get; set;} [Display (Name = "Qq number")] public string Qq {get; set ;} [Display (Name = "add time")] public DateTime AddTime {get; set;} [Display (Name = "Last Logon Time")] public DateTime LastLoginTime {get; set;} [Display (Name = "recently logged on IP")] public string LastLoginIp {get; set;} [Display (Name = "locked")] public bool IsLock {get; set;} [Display (Name = "Super administrator")] public bool IsSuperUser {get; set ;}

All those who have written MVC will know about it. This is an example in the default project.

However, it is difficult for many people to use or not to use it. In the controller, you can determine whether the model has been successfully verified ModelState. IsValid.

But this is not good enough. Sometimes some fields do not need to be verified, and some must be verified. In this way, ModelState. Remove ("verified field"); can be used flexibly. You can ignore that.

In addition, a method for retrieving errors is provided, and a single error is returned. It is not necessary to output every one (I use this to retrieve a single error and transmit it to the client in json format ).

/// <Summary> /// get a single error message /// </summary> /// <param name = "dic"> </param> /// <returns> </returns> public static string GetModelErros (this ModelStateDictionary dic) {string errors = ""; if (! Dic. isValid) {// obtain the first one // errors = dic. keys. first <string> (); errors = dic. values. first (t => t. errors. count> 0 ). errors [0]. errorMessage;} return errors ;}