不能在通用类型或方法中用作类型参数“TElement” [英] Cannot be used as type parameter 'TElement' in the generic type or method

问题描述

我正在使用Entity Model，C＃，.NET Framework 3.5。
我已经从 POCO 生成实体类，但它在ObjectSet和CreateObjectSet上有问题，我通过用ObjectQuery和CreateQuery替换它们来修复。

但是我仍然在 EntityGenerator.Context.cs ，

代码是

  public ObjectResult< lead> ; GetLeads（）
 {
 ** return base.ExecuteFunction< lead>（GetLeads）; ** 
} 
  

错误是

Proj.EntityModel.employee不能用作类型参数'TElement'
在通用类型或方法
'System.Data.Objects.ObjectContext.ExecuteFunction（string，
params System.Data.Objects.ObjectParameter []）'。没有从'Proj.EntityModel.employee'到
'System.Data.Objects.DataClasses.IEntityWithChangeTracker'的隐式
引用转换。

这是什么错误？什么是解决方案？

解决方案

听起来你只需要使 employee 实现 IEntityWithChangeTracker 。

（我怀疑你已经剪切并粘贴错误的代码段，关于 employee 的错误说明，您的代码谈论 lead ，我也鼓励您更改名称，以便他们遵循.NET命名约定。）

I am using Entity Model, C#, .NET Framework 3.5. I have generated entity classes from POCO, but it had issues on ObjectSet and CreateObjectSet which I fixed by replacing them with ObjectQuery and CreateQuery.

But I still have one issue in following code in EntityGenerator.Context.cs,

The code is

public ObjectResult<lead> GetLeads()
        {
            **return base.ExecuteFunction<lead>("GetLeads");**
        }

And the error is

Proj.EntityModel.employee cannot be used as type parameter 'TElement' in the generic type or method 'System.Data.Objects.ObjectContext.ExecuteFunction(string, params System.Data.Objects.ObjectParameter[])'. There is no implicit reference conversion from 'Proj.EntityModel.employee' to 'System.Data.Objects.DataClasses.IEntityWithChangeTracker'.

What's this error? What's solution?

解决方案

It sounds like you just need to make employee implement IEntityWithChangeTracker.

(I suspect you've cut and paste the wrong section of code though, given that the error talks about employee and your code talks about lead. I'd also encourage you to change your names so that they follow .NET naming conventions.)

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