实体框架和Web API的ObjectDisposedException [英] Entity Framework and Web API ObjectDisposedException

问题描述

我有一个使用实体框架5连接到SQL Server数据层。我也有一个LINQ查询，获取一些数据。使用Web API一起使用时，查询失败。我得到的ObjectDisposedException。这里的查询：

 使用（MyContext集装箱=新myContext（））
{
    返回container.Sales
                    .INCLUDE（产品）
                    。凡（S =＆GT; s.Id == id）的
                    .FirstOrDefault（）;
}
 

数据层是一个DLL，由一个业务层，还一个DLL，它是由一个网络API控制器称为露出。我曾假定JSON序列是懒加载包括但没有我的修复工作过。有任何想法吗？我会更新了一个问题，需要的话，如果信息丢失。

下面是业务层调用数据层：

 公开发售GetSale（INT ID）
{
    SaleRepository S =新SaleRepository（）;
    返回s.GetSale（ID）;
}
 

和最终的网络API调用业务层：

 公开发售GetSale（INT ID）
{
    SaleManager S =新SaleManager（）;
    返回s.GetSale（ID）;
}
 

下面是个例外：

  

的ObjectContext的实例已设置，不能再被用于需要连接的操作。

解决方案

这是因为后正在执行延迟加载你的的DbContext 已被释放。

要解决这个问题，你可以这样做禁用延迟加载：

  container.Configuration.LazyLoadingEnabled = FALSE;
 

I have a data layer that uses Entity Framework 5 to connects to Sql Server. I also have a LINQ query that gets some data. This query fails when used with Web API. I get the ObjectDisposedException. Here's the query:

using (MyContext container = new myContext())
{
    return container.Sales
                    .Include("Products")
                    .Where(s => s.Id == id)
                    .FirstOrDefault();
}

The data layer is a dll, exposed by a business layer, also a dll, which is called by a web api controller. I had assumed that the JSON serializer was lazy loading the includes but none of my fixes have worked. Any ideas? I will update the question as need be if info is missing.

Here is the business layer call to the data layer:

public Sale GetSale(int id)
{
    SaleRepository s = new SaleRepository();
    return s.GetSale(id);
}

And finally the web api call to the business layer:

public Sale GetSale(int id)
{
    SaleManager s = new SaleManager();
    return s.GetSale(id);
}

Here is the exception:

The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.

解决方案

This happens because lazy loading is being performed after your DbContext has been disposed.

To resolve the issue you can disable lazy loading by doing this:

container.Configuration.LazyLoadingEnabled = false;

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