.net6 web api uses EF Core to automatically generate tables according to the model class

1. Install the nuget package Microsoft.EntityFrameworkCore
Pomelo.EntityFrameworkCore.MySql of EF Core and mysql database

2. Create the models folder and create entity classes under the folder

  public class Users
    {
    
    
        public int Id {
    
     get; set; }

        [Column(TypeName = "varchar(200)"), Required]
        public string Name {
    
     get; set; }

        [Column(TypeName = "varchar(200)")]
        public string Email {
    
     get; set; }

        [Column(TypeName = "varchar(200)")]
        public string age {
    
     get; set; }
    }

3. Create a database context operation class MyDbContext to inherit DbContext

namespace EfCore
{
    
    
    public class MyDbContext: DbContext
    {
    
    
        //添加Users实体类
        public DbSet<Users> Users {
    
     get; set; }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
    
    
            //modelBuilder.Entity<MyModel>()
            //    .HasKey(x => x.Id);

        //    modelBuilder.Entity<Users>()
        //        .Property(e => e.Email)
        //        .IsRequired()
        //        .HasMaxLength(50);

            modelBuilder.ApplyConfigurationsFromAssembly(typeof(MyDbContext).Assembly);
        }

        //构造函数
        public MyDbContext(DbContextOptions<MyDbContext> option) : base(option)
        {
    
    
            // 如果数据库表不存在则创建
            Database.EnsureCreated();

            // 执行自动迁移以将数据库与实体类定义同步
            Database.Migrate();
        }

    }
}

4. Add a database connection string to the appsettings.json file

  "ConnectionStrings": {
    
    
    "DbConnectionString": " Data Source=localhost;Database=efcore;AllowLoadLocalInfile=true;User ID=root;Password=root;allowPublicKeyRetrieval=true;pooling=true;CharSet=utf8;port=3306;sslmode=none;"
  }

5. Implement dependency injection in the Program.cs class

6. Use in the controller, add a controller named UsersController

 [Route("api/[controller]")]
    [ApiController]
    public class UsersController : ControllerBase
    {
    
    
        private readonly MyDbContext _context;

        public UsersController(MyDbContext context)
        {
    
    
            _context = context;
        }
        [HttpGet("user")]
        public ActionResult<IEnumerable<Users>> Get()
        {
    
    
            return _context.Users.ToList();
        }
    }

7. Start the project and call the api interface, and find that the database table is successfully created to realize automatic migration