支持 <Database> 的模型数据库创建后上下文发生了变化

问题描述

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，并可选择用新数据为其播种."

"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."

我正在尝试使用代码优先功能，以下是我写的:

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，数据库名称是AddressBook"，当我尝试将联系人对象添加到上下文时发生错误.我在这里有什么遗漏吗?

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

现在是:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    Database.SetInitializer<YourDbContext>(null);
    base.OnModelCreating(modelBuilder);
}

在 YourDbContext.cs 文件中.

in your YourDbContext.cs file.