结果为空时LINQ返回什么 [英] What does LINQ return when the results are empty

问题描述

我有一个关于 LINQ 查询的问题.通常，查询返回 IEnumerable 类型.如果返回为空，不确定它是否为空.如果在 IEnumerable 结果中没有发现任何内容，我不确定以下 ToList() 是否会抛出异常或只是一个空的 List ?

I have a question about LINQ query. Normally a query returns a IEnumerable<T> type. If the return is empty, not sure if it is null or not. I am not sure if the following ToList() will throw an exception or just a empty List<string> if nothing found in IEnumerable result?

   List<string> list = {"a"};
   // is the result null or something else?
   IEnumerable<string> ilist = from x in list where x == "ABC" select x;
   // Or directly to a list, exception thrown?
   List<string> list1 = (from x in list where x == "ABC" select x).ToList();

我知道这是一个非常简单的问题，但我暂时没有可用的 VS.

I know it is a very simple question, but I don't have VS available for the time being.

推荐答案

它将返回一个空的枚举.它不会为空.你可以睡觉的声音:)

It will return an empty enumerable. It won't be null. You can sleep sound :)

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