第二节:创建模型,使用Code First,配置映射关系

这一节,实现模型的创建,配置映射关系 使用Code First数据迁移。

创建模型

一,首先创建几个接口:实体接口,聚合根接口,值对象接口

1,实体接口:

![](https://images2018.cnblogs.com/blog/1297333/201806/1297333-20180630190243508-1465071293.png)

2,聚合根接口:

![](https://images2018.cnblogs.com/blog/1297333/201806/1297333-20180630190447629-1515198679.png)

3,值对象接口:

![](https://images2018.cnblogs.com/blog/1297333/201806/1297333-20180630190524322-569928818.png)

二,模型

这里我们的业务场景是:一个用户可以创建一个博客,在博客中可以写多篇文章,一篇文章只能有一个评论,(练习配置映射关系)由于格式的原因我移除了注释信息 用户: public class UserInfo: IAggregationRoot { #region 用户实体 [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)]//添加时自动增长 public int Id { get; set; } public string UserName { get;private set; } public string UserPwd { get; private set; } public Address UserAddr { get; private set; } public string Phone { get; private set; } public string CreateTime { get; private set; } public List UserRoleInfo { get; set; } #endregion public UserInfo(string userName,string userPwd, Address userAddr,string phone) { if (!string.IsNullOrEmpty(userName)) { throw new ArgumentException("客户姓名不能为空!"); } this.UserName = userName; this.UserAddr = userAddr; this.UserPwd = userPwd; this.Phone = phone; this.CreateTime = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"); } public UserInfo CreateUser(string userName, string userPwd, Address userAddr, string phone) { return new UserInfo(userName,userPwd,userAddr,phone); } } 博客: public class BlogInfo:IAggregationRoot { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public int Id { get; set; } public string BolgName { get;private set; } public string BolgUrl { get; set; } public string BolgCrateDate { get;private set; } public string BolgStatus { get;private set; } public int UserId { get;private set; } public virtual List BlogPostList { get; set; } } 文章: public class BlogPostInfo { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public int Id { get; set; } public string ArticleTitleName { get;private set; } public string ArticlePostCount { get;private set; } public string ArticleStatus { get;private set; } public int ReadNum { get;private set; } public string ArticleCrateDate { get;private set; } public int BlogId { get;private set; } //[ForeignKey("BlogId")] public virtual BlogInfo BolgInfo { get; set; } public virtual ArticleReviewsInfo ArticleReviewsInfo { get; set; } } 文章评论: public class ArticleReviewsInfo : IAggregationRoot { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] //[ForeignKey("BlogPostInfo")] public int Id { get; set;} public string ArticleReviewCount { get;private set; } public string ArticleReviewTime { get;private set; } public string ArticleCommentatorId { get;private set; } public string ArticleCommentatorName { get;private set; } public BlogPostInfo BlogPostInfo { get; set; } }

三,使用 Code First,配置映射关系

1,引入Nuget EntityFramework 2,定义MyContext类继承DbContext 3,读取数据库 Web.config中 connectionStrings的配置,数据库连接字符串 4,添加 public DbSet UserInfo Name { get; set; } UserInfo要添加的实体,Name 取的名称 5,配置映射关系 ,有2种方式可以配置,Data Annotation和Fluent API 6, Code First 数据迁移 主要使用的数据迁移的命令:Enable-Migrations Add-Migration 迁移名称 Update-Database Add-Migration InitialCreate -IgnoreChanges 首先先谢谢 libingql,田园的蟋蟀的分享 写的非常的详细,非常的好 。 libingql:http://www.cnblogs.com/libingql/p/3352058.html 配置映射关系 田园的蟋蟀:http://www.cnblogs.com/xishuai/p/3632304.html Code First 数据迁移的所有使用步骤 代码 public class MyContext: DbContext { //读取数据库Web.config connectionStrings的配置 private static readonly string SqlConnectionString = WebConfigurationManager.ConnectionStrings["sqlConnectionString"].ToString(); public MyContext() : base(SqlConnectionString) { // 禁用延迟加载 //this.Configuration.LazyLoadingEnabled = false; } public DbSet UserInfo UserInfo { get; set; } public DbSet RoleInfo RoleInfo { get; set; } public DbSet UserRoleInfo UserRoleInfo { get; set; } public DbSet BlogPostInfo BlogPost { get; set; } public DbSet BlogInfo BlogInfo { get; set; } public DbSet ArticleReviewsInfo ArticleReviewsInfo { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) {
        //值对象的配置
        modelBuilder.ComplexType<Address>().Property(e => e.AddrProvince).HasColumnName("AddrProvince").HasMaxLength(100);
        modelBuilder.ComplexType<Address>().Property(e => e.AddrCity).HasColumnName("AddrCity").HasMaxLength(100);
        modelBuilder.ComplexType<Address>().Property(e => e.AddrCounty).HasColumnName("AddrCounty").HasMaxLength(100);
        modelBuilder.ComplexType<Address>().Property(e => e.AddressDetails).HasColumnName("AddressDetails").HasMaxLength(1000);
        // 禁用默认表名复数形式
        //modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
        //配置UserInfo
        //modelBuilder.Configurations.Add(new UserMap());
        //一对多的关系
        modelBuilder.Entity<BlogInfo>().HasMany(e => e.BlogPostList).WithRequired(e => e.BolgInfo)
            .HasForeignKey(e => e.BlogId);
        modelBuilder.Entity<BlogPostInfo>().HasRequired(e => e.BolgInfo).WithMany(e => e.BlogPostList)
            .HasForeignKey(e => e.BlogId);
         //一对一的关系
        modelBuilder.Entity<ArticleReviewsInfo>().HasRequired(t => t.BlogPostInfo)
            .WithRequiredDependent(t => t.ArticleReviewsInfo);
         //多对多的关系
        modelBuilder.Entity<UserRoleInfo>().HasRequired(e => e.UserInfo).WithMany(e => e.UserRoleInfo)
            .HasForeignKey(e => e.UserId);
        modelBuilder.Entity<UserRoleInfo>().HasRequired(e => e.RoleInfo).WithMany(e => e.UserRoleInfo)
            .HasForeignKey(e => e.RoleId);                          
    }
}
由于格式原因这里应该是: ![](https://images2018.cnblogs.com/blog/1297333/201807/1297333-20180701142759381-870211744.png)

映射关系配置完成后,使用数据迁移请看: 田园的蟋蟀:http://www.cnblogs.com/xishuai/p/3632304.html Code First 数据迁移的所有使用步骤

原文地址:https://www.cnblogs.com/lifeng618/p/9248375.html