代码第一约定混乱 [英] Code First conventions confusion

问题描述

模型：

public class Status
{
    public int Id { get; set; }
}

public class Podcast
{
    public int Id { get; set; }

    public virtual Status Status { get; set; }
}

Podcast表具有StatusId列，此列是外键。在这种情况下，我收到以下错误消息：无效的列名称为'Status_Id'。为什么？ - 很多时候我面对这样的例子的文章。这是第一个问题。
好​​的，没问题 - 我已经添加了一个下划线字符到这些列：Sttaus_Id等等。
现在看来，一切都正常，但是当我通过以下方式修改我的模型时：

The Podcast table has the StatusId column, and this column is a foreign key. In this case I've got the following error message: Invalid column name 'Status_Id'. Why? - Many times I faced that articles with such examples. This is the first question. Ok, no problem - i've added an underscore character to these columns: Sttaus_Id and so on. Now it seems that everything works fine, but when I modify my model by the following way:

public class Podcast
{
    public int Id { get; set; }

    public int Status_Id { get; set; }

    public virtual Status Status { get; set; }
}

现在我收到以下错误：列无效名称'Status_Id1'。
为什么？我不能使用没有这些xx_id属性的DropDownListFor帮助器。

Now I get the following error: Invalid column name 'Status_Id1'. Why? I can't use the DropDownListFor helper without these xx_id properies.

推荐答案

我相信这里的问题是你创建了你的数据库先创建一个名为StatusId的FK参考列，但是您没有告诉EF您正在为FK使用非默认列名。

I believe the issue here is that you have created your DB first and created a column named StatusId for your FK reference but you haven't told EF that you are using a non-default column name for your FK.

以下将给您您的结构（ps我同意您的命名约定，我个人不喜欢_在fk ids）

the following will give you the structure you are after (ps i agree with your naming convention i personally dislike the _ in fk ids)

    public class MyContext : DbContext
    {
        public DbSet<Podcast> Podcasts { get; set; }
        public DbSet<Status> Status { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Podcast>().HasOptional(p => p.Status)
                .WithMany().HasForeignKey(p => p.StatusId);
            base.OnModelCreating(modelBuilder);
        }
    }

    public class Status
    {
        public int Id { get; set; }
    }

    public class Podcast
    {
        public int Id { get; set; }

        public int? StatusId { get; set; }
        public virtual Status Status { get; set; }
    }

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