EF5：DB首先。生成的模型和自定义验证 [英] EF5: DB First. Generated Models and Custom Validation

问题描述

如果我使用第一代开发模式，我可以完全控制我的代码。_
例如，我有型号：User。

  public class User {
 [Key] 
 public int id {get;组; } 
 
 [StringLength（50，ErrorMessage =*长度可能少于50个符号）] 
 [必需（ErrorMessage =*登录不能为空）] 
 public string Login {get;组; } 
 
 [StringLength（50，ErrorMessage =*长度可能少于50个符号）] 
 [必需（ErrorMessage =*名称不能为空）] 
 public string FirstName {get;组; } 
 
 [StringLength（50，ErrorMessage =*长度可能少于50个符号）] 
 [必需（ErrorMessage =*姓氏不能为空）] 
 public string LastName {get;组; } 
 
 [DataType（DataType.EmailAddress）] 
 public string Email {get;组; } 
 public string Phone {get;组; } 
 [必需] 
 public DateTime CreatedAt {get;组; } 
 [必需] 
 public DateTime LastLogin {get;组; } 
 
 public List< Post> PostList {get;组; } 
 
} 
  

我有能力创建自己的验证，如果我使用 DB First Development Model ，我需要使用ADO.NET实体数据模型来生成楷模。我有3个表：

我已经生成了文件：

  DBContext.edmx 
  -  DBContext .Context.tt 
  -  DBContext.Designer.cs 
  -  DBContext.edmx.diagram 
  -  DBContext.tt 
  -  Comment.cs 
  -  DBContext.cs 
  -  Post.cs 
  -  Comment.cs 
  

和代码如下： >

  public partial class DBContext：DbContext 
 {
 public DBContext（）
：base （name = DBContext）
 {
} 
 
 protected override void OnModelCreating（DbModelBuilder modelBuilder）
 {
 throw new UnintentionalCodeFirstException（）; 
} 
 
 public DbSet< Comment>评论{get;组; } 
 public DbSet< Post>邮寄{get;组; } 
 public DbSet< User>用户{get;组; 
 
 
 public partial class User 
 {
 public User（）
 {
 this.Comment = new HashSet< Comment> ）; 
 this.Comment1 = new HashSet< Comment>（）; 
 this.Post = new HashSet< Post>（）; 
 this.Post1 = new HashSet< Post>（）; 
} 
 
 public int id {get;组; } 
 public string Login {get;组; } 
 public string FirstName {get;组; } 
 public string LastName {get;组; } 
 public string Email {get;组; } 
 public string Phone {get;组; } 
 public System.DateTime CreatedAt {get;组; } 
 public System.DateTime LastLogin {get;组; } 
 
 public virtual ICollection< Comment>评论{get;组; } 
 public virtual ICollection< Comment> Comment1 {get;组; } 
 public virtual ICollection< Post>邮寄{get;组; } 
 public virtual ICollection< Post> Post1 {get;组; } 
 public virtual User User1 {get;组; } 
 public virtual User User2 {get;组; 
 
 
 public partial class Post 
 {
 public Post（）
 {
 this.Comment = new HashSet< Comment> ）; 
} 
 
 public int id {get;组; } 
 public string标题{get;组; } 
 public string Text {get;组; } 
 public string TextFormatted {get;组; } 
 public System.DateTime CreatedAt {get;组; } 
 public System.DateTime UpdatedAt {get;组; } 
 public Nullable< int> CreatedById {get;组; } 
 public Nullable< int> UpdatedById {get;组; } 
 public Nullable< int> UserId {get;组; } 
 
 public virtual User User {get;组; } 
 public virtual User User1 {get;组; } 
 public virtual ICollection< Comment>评论{get;组; 
} 
 
 public partial class注释
 {
 public int id {get;组; } 
 public string标题{get;组; } 
 public string Text {get;组; } 
 public string TextFormatted {get;组; } 
 public System.DateTime CreatedAt {get;组; } 
 public System.DateTime UpdatedAt {get;组; } 
 public Nullable< int> CreatedById {get;组; } 
 public Nullable< int> UpdatedById {get;组; } 
 public Nullable< int> PostId {get;组; } 
 
 public virtual User User {get;组; } 
 public virtual User User1 {get;组; } 
 public virtual Post Post {get;组; } 
 public virtual注释1 {get;组; } 
 public virtual Comment Comment2 {get;组; } 
} 
  

问题：

1.据我所知如果我使用DB First Development Model，我不能使用我自己的模型进行数据访问，只是由ADO.NET Entity Data Model生成的模型/类？？
我试图使用自己的模型UserOwn除了生成User，所以我得到一个错误无法检索TestDBFirst02.Models.UserOwn的元数据。期待。

2.我可以在一个项目中使用开发模型：Code First和DB First吗？

3.如果我需要使用生成的模型，我需要什么做，当我想使用我自己的验证？我试图修改生成的模型，它的作用是：

  [StringLength（50，ErrorMessage =*长度可能小于50符号）] 
 [必需（ErrorMessage =*登录不能为空）] 
 public string Login {get;组; } 
  

但是，如果我需要从DB更新模型，当然我的验证码将被ADO覆盖。 NET实体数据模型和属性消失。

解决方案

回答<3>第三方问题：需要使用 [MetadataTypeAttribute（typeof（UserValidation）] 属性并创建验证类，所以代码是：

  [MetadataType（typeof（UserValidation））] 
 public partial class User {} 
 
 public class UserValidation 
 {
 [StringLength 50，ErrorMessage =*长度可能少于50个符号）] 
 [必需（ErrorMessage =*登录不能为空）] 
 public string Login {get; set;} 
} 
  

与相同！命名空间，因为用户模型。
阅读更多：

• http://www.asp.net/mvc/tutorials/mvc-5/database-第一次开发/增强数据验证


• http：// jnye.co/Posts/19/adding-validation-to-models-created-by-entity-framework-database-first-c


• http://weblogs.asp.net/scottgu/asp-net-mvc-2-模型验证


• 数据库首次验证


• 添加验证使用数据库优先模型（EF 5）建模


• http://www.elevenwinds.com/data-validation-in-asp-net-mvc-database-first

If I use Code First Development Model, I have a full control of my code.
For Example, I have model: User.

public class User {
    [Key]
    public int id { get; set; }

    [StringLength(50, ErrorMessage = "* Length might be less then 50 symbols")]
    [Required(ErrorMessage = "* Login can't be empty")]
    public string Login { get; set; }

    [StringLength(50, ErrorMessage = "* Length might be less then 50 symbols")]
    [Required(ErrorMessage = "* Name can't be empty")]
    public string FirstName { get; set; }

    [StringLength(50, ErrorMessage = "* Length might be less then 50 symbols")]
    [Required(ErrorMessage = "* Last name can't be empty")]
    public string LastName { get; set; }

    [DataType(DataType.EmailAddress)]
    public string Email { get; set; }
    public string Phone { get; set; }
    [Required]
    public DateTime CreatedAt { get; set; }
    [Required]
    public DateTime LastLogin { get; set; }

    public List<Post> PostList { get; set; }

}

I have ability to create my own validation, like at model "User".

In case, if I use DB First Development Model, I need to use ADO.NET Entity Data Model to generate models. I have 3 tables:

I have generated files:

DBContext.edmx
 - DBContext.Context.tt
 - DBContext.Designer.cs
 - DBContext.edmx.diagram
 - DBContext.tt
   - Comment.cs
   - DBContext.cs
   - Post.cs
   - Comment.cs

and code below:

public partial class DBContext : DbContext
{
    public DBContext()
        : base("name=DBContext")
    {
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        throw new UnintentionalCodeFirstException();
    }

    public DbSet<Comment> Comment { get; set; }
    public DbSet<Post> Post { get; set; }
    public DbSet<User> User { get; set; }
}

public partial class User
{
    public User()
    {
        this.Comment = new HashSet<Comment>();
        this.Comment1 = new HashSet<Comment>();
        this.Post = new HashSet<Post>();
        this.Post1 = new HashSet<Post>();
    }

    public int id { get; set; }
    public string Login { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
    public string Phone { get; set; }
    public System.DateTime CreatedAt { get; set; }
    public System.DateTime LastLogin { get; set; }

    public virtual ICollection<Comment> Comment { get; set; }
    public virtual ICollection<Comment> Comment1 { get; set; }
    public virtual ICollection<Post> Post { get; set; }
    public virtual ICollection<Post> Post1 { get; set; }
    public virtual User User1 { get; set; }
    public virtual User User2 { get; set; }
}

public partial class Post
{
    public Post()
    {
        this.Comment = new HashSet<Comment>();
    }

    public int id { get; set; }
    public string Title { get; set; }
    public string Text { get; set; }
    public string TextFormatted { get; set; }
    public System.DateTime CreatedAt { get; set; }
    public System.DateTime UpdatedAt { get; set; }
    public Nullable<int> CreatedById { get; set; }
    public Nullable<int> UpdatedById { get; set; }
    public Nullable<int> UserId { get; set; }

    public virtual User User { get; set; }
    public virtual User User1 { get; set; }
    public virtual ICollection<Comment> Comment { get; set; }
}

public partial class Comment
{
    public int id { get; set; }
    public string Title { get; set; }
    public string Text { get; set; }
    public string TextFormatted { get; set; }
    public System.DateTime CreatedAt { get; set; }
    public System.DateTime UpdatedAt { get; set; }
    public Nullable<int> CreatedById { get; set; }
    public Nullable<int> UpdatedById { get; set; }
    public Nullable<int> PostId { get; set; }

    public virtual User User { get; set; }
    public virtual User User1 { get; set; }
    public virtual Post Post { get; set; }
    public virtual Comment Comment1 { get; set; }
    public virtual Comment Comment2 { get; set; }
}

Questions:
1. As I understand, if I use DB First Development Model, I can't use my own models for data access, just models/classes, generated by ADO.NET Entity Data Model?
I tried to use my own model "UserOwn" except generated "User", so I got an error "Unable to retrieve metadata for 'TestDBFirst02.Models.UserOwn'". Expected.
2. Can I use both Development Model: Code First and DB First inside one project?
3. If I need to use generated models, what I need to do, when I want to use my own validation? I tried to modificate generated model, and it works:

[StringLength(50, ErrorMessage = "* Length might be less then 50 symbols")]
[Required(ErrorMessage = "* Login can't be empty")]
public string Login { get; set; } 

But, if I need to update model from DB, of course my validation code overwrites by ADO.NET Entity Data Model and attributes disappear. How can I overcome the situation with my own validation?

解决方案

Answer the 3-rd question: need to use [MetadataTypeAttribute(typeof(UserValidation)] attribute and create validation class, so code is:

[MetadataType(typeof(UserValidation))]
public partial class User {}

public class UserValidation
{
    [StringLength(50, ErrorMessage = "* Length might be less then 50 symbols")]
    [Required(ErrorMessage = "* Login can't be empty")]
    public string Login { get; set; }
}

with the same! namespace, as User model has.
Read more:

• http://www.asp.net/mvc/tutorials/mvc-5/database-first-development/enhancing-data-validation
• http://jnye.co/Posts/19/adding-validation-to-models-created-by-entity-framework-database-first-c
• http://weblogs.asp.net/scottgu/asp-net-mvc-2-model-validation
• Database First Validation
• Adding validation to model with Database First model (EF 5)
• http://www.elevenwinds.com/data-validation-in-asp-net-mvc-database-first

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