1.新建项目，MVC 选择基本模板
2.新建类：Model/Student.cs，数据库信息有三个实体：分别是年级、班级和学
生。
using System;using System.Collections.Generic;using
System.ComponentModel.DataAnnotations;using System.Linq;using
System.Web;
namespace CascadeExample.Models
{
public class Grade
{
[Key]
public int GradeId { get; set; }
public string GradeName { get; set; }
public List<Class> Classes { get; set; }
}
public class Class
{
[Key]
public int ClassId { get; set; }
public string ClassName { get; set; }
public int GradeId { get; set; }
public Grade Grades { get; set; }
public List<Student> Students { get;set; }
}
public class Student
{
[Key]
public int StudentId { get; set; }
public string StudentName { get; set; }
public int ClassId { get; set; }
public Class Classes { get; set; }
}
}
3.新建类:Model/StudentContext.cs
using System;using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;using System.Web;
