使用实体框架核心将嵌套实体(如一对多)插入数据库

// 定义学生实体类
public class Student
{
    public int Id { get; set; }
    public string Name { get; set; }
    public List<Course> Courses { get; set; }
}

// 定义课程实体类
public class Course
{
    public int Id { get; set; }
    public string Name { get; set; }
}

// 创建数据库上下文类
public class SchoolContext : DbContext
{
    public DbSet<Student> Students { get; set; }
    public DbSet<Course> Courses { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Student>()
            .HasMany(s => s.Courses)
            .WithOne()
            .HasForeignKey(c => c.StudentId);
    }
}

// 在应用程序中插入数据
public class Program
{
    static void Main(string[] args)
    {
        using (var context = new SchoolContext())
        {
            var student = new Student
            {
                Name = "John Doe",
                Courses = new List<Course>
                {
                    new Course { Name = "Math" },
                    new Course { Name = "Science" }
                }
            };

            context.Students.Add(student);
            context.SaveChanges();
        }
    }
}