3.使用Configuration.cs中的Seed方法
在数据库迁移过程中，使用update-database，会运行seed方法。seed方法能够将初始数据注入数据库。
protected override void Seed(SchoolContext context)
{
var students = new List<Student>
{
new Student { FirstMidName = "Carson", LastName = "Alexander",
EnrollmentDate = DateTime.Parse("2010-09-01") },
new Student { FirstMidName = "Meredith", LastName = "Alonso",
EnrollmentDate = DateTime.Parse("2012-09-01") },
new Student { FirstMidName = "Arturo", LastName = "Anand",
EnrollmentDate = DateTime.Parse("2013-09-01") },
new Student { FirstMidName = "Gytis", LastName = "Barzdukas",
EnrollmentDate = DateTime.Parse("2012-09-01") },
new Student { FirstMidName = "Yan", LastName = "Li",
EnrollmentDate = DateTime.Parse("2012-09-01") },
new Student { FirstMidName = "Peggy", LastName = "Justice",
EnrollmentDate = DateTime.Parse("2011-09-01") },
new Student { FirstMidName = "Laura", LastName = "Norman",
EnrollmentDate = DateTime.Parse("2013-09-01") },
new Student { FirstMidName = "Nino", LastName = "Olivetto",
EnrollmentDate = DateTime.Parse("2005-09-01") }
};
students.ForEach(s => context.Students.AddOrUpdate(p => p.LastName, s));
context.SaveChanges();
......
要注意当两个类之间有关联时，注入数据需要特殊处理。
var instructors = new List<Instructor>
{
new Instructor { FirstMidName = "Kim", LastName = "Abercrombie",
HireDate = DateTime.Parse("1995-03-11") },
new Instructor { FirstMidName = "Fadi", LastName = "Fakhouri",
HireDate = DateTime.Parse("2002-07-06") },
new Instructor { FirstMidName = "Roger", LastName = "Harui",
HireDate = DateTime.Parse("1998-07-01") },
new Instructor { FirstMidName = "Candace", LastName = "Kapoor",
HireDate = DateTime.Parse("2001-01-15") },
new Instructor { FirstMidName = "Roger", LastName = "Zheng",
HireDate = DateTime.Parse("2004-02-12") }
};
instructors.ForEach(s => context.Instructors.AddOrUpdate(p => p.LastName, s));
context.SaveChanges(); var departments = new List<Department>
{
new Department { Name = "English", Budget = ,
StartDate = DateTime.Parse("2007-09-01"),
PersonID = instructors.Single( i => i.LastName == "Abercrombie").PersonID },
new Department { Name = "Mathematics", Budget = ,
StartDate = DateTime.Parse("2007-09-01"),
PersonID = instructors.Single( i => i.LastName == "Fakhouri").PersonID },
new Department { Name = "Engineering", Budget = ,
StartDate = DateTime.Parse("2007-09-01"),
PersonID = instructors.Single( i => i.LastName == "Harui").PersonID },
new Department { Name = "Economics", Budget = ,
StartDate = DateTime.Parse("2007-09-01"),
PersonID = instructors.Single( i => i.LastName == "Kapoor").PersonID }
};
departments.ForEach(s => context.Departments.AddOrUpdate(p => p.Name, s));
context.SaveChanges();
4.实体类间关系分析
（1）一对一
（2）一对多
（3）多对多