我得到了以下简单模型,该模型正在代码优先方法中实现。部门和课程是一对多的关系。一个系可以有很多门课程,而一门课程可以只属于一个系。这是模型。
public class Department
{
public int DepartmentId { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public virtual ICollection<Course> Courses { get; set; }
}
public class Course
{
public int CourseId { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public int DepartmentId { get; set; }
public virtual Department Department { get; set; }
}
我的问题是我想给它们播种。我希望种子函数中至少有 5 个值。这是种子函数。
public class DataInitializer : DropCreateDatabaseIfModelChanges<StudentRecordContext>
{
protected override void Seed(StudentRecordContext context)
{
var departments = new List<Department>
{
new Department { DepartmentId = 1, Title = "English", Description ="English Department", Courses = new List<Course>() },
new Department { DepartmentId= 2,Title = "Chemistry", Description ="chemistry department", Courses = new List<Course>() },
new Department { DepartmentId= 3,Title = "Mahematics", Description ="mathematics department", Courses = new List<Course>() },
new Department { DepartmentId= 4,Title = "Philosophy", Description ="philosophy department", Courses = new List<Course>() },
new Department { DepartmentId= 5,Title = "Biology", Description ="biology department", Courses = new List<Course>() }
};
departments.ForEach( t => context.Departments.Add(t));
context.SaveChanges();
var courses = new List<Course>
{
new Course { CourseId = 1055, Title = "Classic English", Description = "Some Description", DepartmentId = 1 },
new Course { CourseId = 2055, Title = "Applied Chemistry", Description = "Some Description", DepartmentId = 2 },
new Course { CourseId = 2056, Title = "Applied Mathematics", Description = "Some Description", DepartmentId = 3 },
new Course { CourseId = 3041, Title = "MetaPhysics", Description = "Some Description", DepartmentId = 4 },
new Course { CourseId = 3024, Title = "Molecular Biology", Description = "Some Description", DepartmentId = 5 },
};
courses.ForEach(t => context.Courses.Add(t));
context.SaveChanges();
但这不起作用。我是 EF 和 Code First 的新手...并且截止日期即将到来...任何人都可以帮助我,因为播种数据库的正确方法是什么。