如何在实现IEnumerable&LT我的字典包装类实现IEnumerable;美孚&GT ;?

问题描述

我试图创建一个词典℃的包装;弦乐，富方式>

字典<弦乐，富> 工具的IEnumerable< KeyValuePair<弦乐，富>> ，但我想我的包装类来实现的IEnumerable<富> 。所以，我想这样的：

 公共类FooCollection：IEnumerable的<富> 
 {
私人字典<字符串，富> fooDictionary =新词典<字符串，富>（）; 
 
公众的IEnumerator<富>的GetEnumerator（）
 {
返回fooDictionary.Values.GetEnumerator（）; 
} 
 
 //其他包装方法省略
 
} 
  

不过，我得到这个错误：

However I don't understand this error, because FooCollection.GetEnumerator() returns an IEnumerator<Foo>, and IEnumerator<Foo> is an IEnumerator.

EDIT:

The solution of explicitly implementing IEnumerator.GetEnumerator() works. However I'm now wondering why when I "Go to definition" on a List<T> I see only one definition of GetEnumerator:public List<T>.Enumerator GetEnumerator();

Apparently List<T> can have a single GetEnumerator method that returns something that implements both IEnumerator<T> and IEnumerator, but I have to have one method for each?

EDIT:

As answered by LukeH below, List<T> does include the explicit interface implementations. Apparently Visual Studio just doesn't list those when generating method stubs from the metadata. (See this previous question: Why does the VS Metadata view does not display explicit interface implemented members )

Before posting this question I had tried checking List<T> (via "Go to Definition" in Visual Studio) to see if I needed to implement multiple versions of GetEnumerator. I guess this wasn't the most reliable way to check.

Anyway, I'm marking this as answered. Thanks for your help.

解决方案

Add the following explicit interface implementation:

IEnumerator IEnumerable.GetEnumerator()
{
    return this.GetEnumerator();
}

Although IEnumerator<T> is an IEnumerator, the contract for IEnumerable returns an IEnumerator specifically, not an IEnumerator<T>

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