breezejs：导航属性未添加到实体 [英] breezejs: navigation property not added to entity

问题描述

我已经配置了我的WebAPI ODATA服务（使用5.0.0-rc1进行$ expand和$ select支持），一切似乎工作正常但导航属性。

I've configured my WebAPI ODATA service (using 5.0.0-rc1 for $expand and $select support) and everything seems to work fine but navigation properties.

元数据确实包含我的导航属性（授权时的OpenPositions）：

The metadata does contain my navigation property (OpenPositions on Mandate) :

然后我的微风查询如下：

Then my breeze query is the following:

function search() {       
    var query =  breeze.EntityQuery.from("Mandates").expand("OpenPositions").inlineCount();

    return manager.executeQuery(query.using(service)).then(function (result) {
        logger.info(result);
    }).fail(function (error) {
        logger.error(error);
    });
}

WebAPI控制器：

The WebAPI controller :

[Queryable(AllowedQueryOptions= AllowedQueryOptions.All)]
    public override IQueryable<Mandate> Get()
    {
          return new List<Mandate>() { new Mandate() { 
            Id = 1, 
            PolicyNumber = "350000000",
            OpenPositions = new List<OpenPosition>(){ 
                new OpenPosition(){ Id = 1, Amount = 2300, Mandate_Id = 1 },
                new OpenPosition(){ Id = 2, Amount = 2100, Mandate_Id = 1 }
            }},
            new Mandate() { 
                Id = 2, 
                PolicyNumber = "240000000" ,
                OpenPositions = new List<OpenPosition>(){ 
                new OpenPosition(){ Id = 3, Amount = 2500, Mandate_Id = 2 },
                new OpenPosition(){ Id = 2, Amount = 2100,  Mandate_Id = 2}
            }

            } }.AsQueryable<Mandate>();
    }

没什么了不起的。但是虽然我的Mandate实体回到结果集中，但它们没有OpenPositions集合。

Nothing spectacular. But although my Mandate entities are coming back in the resultset, they do not have their OpenPositions collection.

作为测试，如果我将 .select（OpenPositions）添加到我的微风查询中，那么我得到错误：

As a test, if I add .select("OpenPositions") to my breeze query, then I get an error:

无法找到属性：entityType上的OpenPositions：Mandate：#WebAPINoBreeze.Models

为什么会这样？

query.entityType.NavigationProperties是一个空数组，所以这可能是一个线索......似乎是微风无法从元数据中构建导航属性。

query.entityType.NavigationProperties is an empty array, so that's probably a clue... It seems breeze could not build navigationproperties out of the metadata.

外国钥匙补充说。问题仍然存在：

foreign key added. problem still there:

 public class Mandate
{
    public int Id { get; set; }
    public string PolicyNumber { get; set; }
    public EStatus Status { get; set; }
    public virtual  List<OpenPosition> OpenPositions { get; set; }
}

public class OpenPosition
{
    public int Id { get; set; }
    public decimal Amount { get; set; }
    [ForeignKey("Mandate")]
    public int Mandate_Id { get; set; }
}

** **

由于某些原因，在编译时删除了[ForeignKey（Mandate）]属性（我认为这是因为生成了模型类。我找到了一种解决方法，现在元数据包含外键MandateId在OpenPositions中授权：

For some reasons the [ForeignKey("Mandate")] attribute was removed at compile time (I think it's because the model class is generated. I've found a workaround and the metadata now contains the foreign key MandateId to Mandate in the OpenPositions :

推荐答案

您必须定义外键，因为Breeze关联需要FK。 http://www.breezejs.com/documentation/navigation-properties

You must define a foreign key as Breeze associations require FKs. http://www.breezejs.com/documentation/navigation-properties

您的双向关联应如下所示：

Your bi-directional association should look like this:

 public class Mandate
{
    public int Id { get; set; }
    public string PolicyNumber { get; set; }

    public virtual  ICollection<OpenPosition> OpenPositions { get; set; }
}

public class OpenPosition {
    public int Id { get; set; }
    public decimal Amount { get; set; }

    public int MandateId { get; set; }
    public Mandate Mandate {get; set; }
}

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