ASP.NET使用EntityFrameworkCore CodeFrist-木庄网络博客

本文摘自PHP中文网，作者大家讲道理，侵删。

1,首先根据个人需要下载对应的微软官方.net core sdk和runtime(https://www.microsoft.com/net/download/core)

2,创建一个asp.net Core的项目

3,创建实体Entity,用户和角色

public class User
{
    public int Id { get; set; }
    /// <summary>
    /// 角色Id
    /// </summary>
    public int RoleId { get; set; }
    public virtual Role Role { get; set; }
    /// <summary>
    /// 状态
    /// </summary>
    public int Status { get; set; }
    /// <summary>
    /// 登陆名
    /// </summary>
    public string Login { get; set; }
    /// <summary>
    /// 登陆密码
    /// </summary>
    public string Pwd { get; set; }
}

public class Role
{
    public int Id { get; set; }
    /// <summary>
    /// 角色名
    /// </summary>
    public string Name { get; set; }
    /// <summary>
    /// 一个角色的多个用户
    /// </summary>
    public virtual ICollection<User> Users { get; set; }
}

4，创建DbContext

public class EFDbContext: DbContext
{
    public EFDbContext(DbContextOptions<EFDbContext> options) : base(options)
    { }
    public DbSet<Role> Roles { get; set; }
    public DbSet<User> Users { get; set; }
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        Role(modelBuilder);
        User(modelBuilder);
    }
 
    private void User(ModelBuilder modelBuilder)
    {
        var userBuilder = modelBuilder.Entity<User>().ToTable("User");
        // Properties
        userBuilder.Property(t => t.Id).ValueGeneratedOnAdd();
        userBuilder.Property(t => t.RoleId).IsRequired();
        userBuilder.Property(t => t.Status).IsRequired();
        userBuilder.Property(t => t.Login).IsRequired().HasMaxLength(30);
        userBuilder.Property(t => t.Pwd).IsRequired().HasMaxLength(60);
        // Primary Key
        userBuilder.HasKey(t => t.Id);
        // Index
        userBuilder.HasIndex(t => t.Login);
        // Relationships
        userBuilder.HasOne(t => t.Role).WithMany(t => t.Users).HasForeignKey(t => t.RoleId);
    }
 
    private void Role(ModelBuilder modelBuilder)
    {
        var roleBuilder = modelBuilder.Entity<Role>().ToTable("Role");
        // Properties
        roleBuilder.Property(t => t.Id).ValueGeneratedOnAdd();
        roleBuilder.Property(t => t.Name).IsRequired().HasMaxLength(30);
        // Primary Key
        roleBuilder.HasKey(t => t.Id);
    }
}

5，创建DbInitializer，用于创建初始数据

public class DbInitializer
{
    public async static Task InitData(EFDbContext context)
    {
        if (context.Database != null && context.Database.EnsureCreated())
        {
            //角色配置
            context.Roles.AddRange(new Role[]
            {
                new Role { Name="超级管理员" },
                new Role { Name="管理员" }
            });
            //默认用户
            context.Users.AddRange(new User[]
            {
                new User { RoleId=1, Login="administrator", Pwd="111111" },
                new User { RoleId=2, Login="admin", Pwd="111111" }
            });
 
            await context.SaveChangesAsync();
        }
    }

6，修改Startup类方法

在ConfigureServices添加如下代码

1 2	`// DbContext` `services.AddDbContext<EFDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));`

在Configure方法内添加

public async void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    loggerFactory.AddConsole(Configuration.GetSection("Logging"));
    loggerFactory.AddDebug();
 
    app.UseMvc();
 
    await DbInitializer.InitData(app.ApplicationServices.GetService<EFDbContext>());
}

7，修改appsettings.json

{
  "ConnectionStrings": {
    "DefaultConnection": "Data Source=.;Initial Catalog=LniceCore;Integrated Security=SSPI;"
  },
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Debug",
      "System": "Information",
      "Microsoft": "Information"
    }
  }
}