错误信息：

“支持 ‘AddressBook’ 上下文的模型自创建数据库以来已更改。手动删除/更新数据库，或使用 IDatabaseInitializer 实例调用
Database.SetInitializer。例如，RecreateDatabaseIfModelChanges
策略将自动删除并重新创建数据库，并且可选择用新数据播种它。”

我正在尝试使用代码优先功能，以下是我写的：

var modelBuilder = new ModelBuilder();
var model = modelBuilder.CreateModel();
using (AddressBook context = new AddressBook(model))
{
    var contact = new Contact
    {
        ContactID = 10000,
        FirstName = "Brian",
        LastName = "Lara",
        ModifiedDate = DateTime.Now,
        AddDate = DateTime.Now,
        Title = "Mr."

    };
    context.contacts.Add(contact);
    int result = context.SaveChanges();
    Console.WriteLine("Result :- "+ result.ToString());
}

上下文类：

public class AddressBook : DbContext
{
    public AddressBook()
    { }
    public AddressBook(DbModel AddressBook)
        : base(AddressBook)
    {

    }
    public DbSet<Contact> contacts { get; set; }
    public DbSet<Address> Addresses { get; set; }
}

和连接字符串：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <connectionStrings>
    <add name="AddressBook" providerName="System.Data.SqlClient"  
         connectionString="Data Source=MyMachine;Initial Catalog=AddressBook;
         Integrated Security=True;MultipleActiveResultSets=True;"/>
    </connectionStrings>
</configuration>

因此，数据库名称是“AddressBook”，当我尝试将联系人对象添加到上下文时会发生错误。我在这里错过了什么吗？