首先映射私有属性实体框架代码

Question

我正在使用EF 4.1,并且因缺乏枚举支持而寻找一个很好的解决方法.int的支持属性似乎是合乎逻辑的.

    [Required]
    public VenueType Type
    {
        get { return (VenueType) TypeId; }
        set { TypeId = (int) value; }
    }

    private int TypeId { get; set; }

但是,如何将此属性设为私有并仍然映射它.换一种说法:

如何首先使用EF 4.1代码映射私有属性？

Answer 1

这是一个可以在EF 6+中使用的约定来映射选定的非公共属性(只需将[Column]属性添加到属性).

在您的情况下,您将TypeId更改为:

    [Column]
    private int TypeId { get; set; }

在你的DbContext.OnModelCreating,你需要注册约定:

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Add(new NonPublicColumnAttributeConvention());
    }

最后,这是惯例:

/// <summary>
/// Convention to support binding private or protected properties to EF columns.
/// </summary>
public sealed class NonPublicColumnAttributeConvention : Convention
{

    public NonPublicColumnAttributeConvention()
    {
        Types().Having(NonPublicProperties)
               .Configure((config, properties) =>
                          {
                              foreach (PropertyInfo prop in properties)
                              {
                                  config.Property(prop);
                              }
                          });
    }

    private IEnumerable<PropertyInfo> NonPublicProperties(Type type)
    {
        var matchingProperties = type.GetProperties(BindingFlags.SetProperty | BindingFlags.GetProperty | BindingFlags.NonPublic | BindingFlags.Instance)
                                     .Where(propInfo => propInfo.GetCustomAttributes(typeof(ColumnAttribute), true).Length > 0)
                                     .ToArray();
        return matchingProperties.Length == 0 ? null : matchingProperties;
    }
}

Answer 2

您不能先在EF代码中映射私有属性.您可以尝试将其更改为protected并在继承的类中进行配置 EntityConfiguration.
编辑
现在它已更改,请参阅此/sf/answers/966753651/

Answer 3

另一个解决方法可能是将您的字段设置为内部：

    [NotMapped]
    public dynamic FacebookMetadata {
        get
        {
            return JObject.Parse(this.FacebookMetadataDb);
        }
        set
        {
            this.FacebookMetadataDb = JsonConvert.SerializeObject(value);
        }
    }

    ///this one
    internal string FacebookMetadataDb { get; set; }

并将其添加到游览模型中：

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Conventions.Remove<System.Data.Entity.ModelConfiguration.Conventions.ManyToManyCascadeDeleteConvention>();

        ///here
        modelBuilder.Entity<FacebookPage>().Property(p => p.FacebookMetadataDb);

        base.OnModelCreating(modelBuilder);
    }