在EFCore中通过连接表使用自动映射程序

public class Student
{
    public int StudentId { get; set; }
    public string Name { get; set; }
    public ICollection<Course> Courses { get; set; }
}

public class Course
{
    public int CourseId { get; set; }
    public string Name { get; set; }
    public ICollection<Student> Students { get; set; }
}

public class Student
{
    //...
    public ICollection<StudentCourse> StudentCourses { get; set; }
}

public class Course
{
    //...
    public ICollection<StudentCourse> StudentCourses { get; set; }
}

public class StudentCourse
{
    public int StudentId { get; set; }
    public Student Student { get; set; }
    public int CourseId { get; set; }
    public Course Course { get; set; }
}

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<StudentCourse>()
        .HasKey(sc => new { sc.StudentId, sc.CourseId });

    modelBuilder.Entity<StudentCourse>()
        .HasOne(sc => sc.Student)
        .WithMany(s => s.StudentCourses)
        .HasForeignKey(sc => sc.StudentId);

    modelBuilder.Entity<StudentCourse>()
        .HasOne(sc => sc.Course)
        .WithMany(c => c.StudentCourses)
        .HasForeignKey(sc => sc.CourseId);
}