该模型支持的＆lt;数据库＆GT;背景已经改变，因为在创建数据库。 [英] The model backing the <Database> context has changed since the database was created.

问题描述

该错误消息：

的模式支持的地址簿背景已经改变，因为在创建数据库。手动删除/更新数据库，或拨打Database.SetInitializer与IDatabaseInitializer实例。例如，RecreateDatabaseIfModelChanges战略将自动删除并重新创建数据库，以及可选的种子用新的数据。

"The model backing the 'AddressBook' context has changed since the database was created. Either manually delete/update the database, or call Database.SetInitializer with an IDatabaseInitializer instance. For example, the RecreateDatabaseIfModelChanges strategy will automatically delete and recreate the database, and optionally seed it with new data."

我想用code-第一特征，下面是我写的：

I am trying to use the code-first feature and following is what I wrote:

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>

所以，数据库名称为通讯录，当我试图接触对象添加到上下文中的错误发生。我缺少什么吗？

So, the database name is "AddressBook" and the error happens when I trying to add the contact object to the context. Am I missing anything here?

推荐答案

刚刚发现更新这里的答案和想法。只需要做到以下几点。

Just found out the answer and thought of updating here. Just need to do the following.

public class AddressBook: DbContext
{
   protected override void OnModelCreating(ModelBuilder modelBuilder)
   {
    modelBuilder.IncludeMetadataInDatabase = false;
   }
}

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