如何将Entity框架中的DbSet转换为ObjectQuery [英] How to convert DbSet in Entity framework to ObjectQuery

问题描述

我正在使用CodeFirst方法，并遇到一个问题，我需要将DbSet转换为ObjectQuery。
这是我做的转换。

I am using CodeFirst approach and struck with an issue where I need to convert DbSet to ObjectQuery. This is what I did for conversion.

ObjectContext objectContext = ((IObjectContextAdapter)db).ObjectContext;
ObjectSet<Request> objectSet = objectContext.CreateObjectSet<Request>();

其中db是从DbContext继承的上下文，Request是类。

where db is the context inheriting from DbContext and Request is class.

所以，当我尝试调用ObjectQuery作为ObjectQueryMethod（objectSet）的方法时，会抛出以下错误。

So, when I try to call the method that expects ObjectQuery as ObjectQueryMethod(objectSet), it throws the following error.

条件类型无法确定表达式，因为'System.Data.Entity.DbSet<>'和'System.Data.Objects.ObjectQuery<>'之间没有隐式转换

"Type of conditional expression cannot be determined because there is no implicit conversion between 'System.Data.Entity.DbSet<>' and 'System.Data.Objects.ObjectQuery<>'"

任何帮助非常感谢！

推荐答案

我找到答案。当然，可以使用下面的代码行将Entity框架中的DbSet转换为ObjectQuery。

I found the answer. Of course, it is possible to convert DbSet in Entity framework to ObjectQuery using the below lines of code.

ObjectContext objectContext = ((IObjectContextAdapter)db).ObjectContext;  
ObjectSet<Request> objectSet = objectContext.CreateObjectSet<Request>("Requests");

其中，

• db - 从 DbContext 继承的上下文类。在Context类中定义的


• 请求 - DbSet< Request>


• objectSet - 现在可以以 ObjectQuery
  

• db - Context class inherting from DbContext.
• Requests - DbSet<Request> defined in Context class.
• objectSet - Can now be passed as ObjectQuery.

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