我有一个的问题类有一个可以包含多个回答公众列表属性

I have a Question class that has public List property that can contain several Answers.

我有一个问题库，负责从XML文件读取的问题和答案。

I have a question repository which is responsible for reading the questions and its answers from an xml file.

所以，我有问题（列表），每个问题的对象有答案的集合，我想查询的问题的这个集合的答案（即由它的名字）使用LINQ的集合。我不知道如何正确地做到这一点。

So I have a collection of Questions (List) with each Question object having a collection of Answers and I'd like to query this collection of Questions for an Answer (ie by its Name) by using Linq. I don't know how to do this properly.

我可以用一个foreach做，但我想知道是否有纯粹的LINQ的方式，因为我学习它。

I could do it with a foreach but I'd like to know whether there is a pure Linq way since I'm learning it.

推荐答案

要找到一个答案。

questions.SelectMany(q => q.Answers).Where(a => a.Name == "SomeName")

要找到答案的问题。

question.Where(q => q.Answers.Any(a => a.Name == "SomeName"))

事实上，你会得到答案或问题的集合，你将不得不使用一（）， FirstOrDefault（），单（）或的SingleOrDefault（）根据您的需要得到一个明确的答案或问题。

In fact you will get collections of answers or questions and you will have to use First(), FirstOrDefault(), Single(), or SingleOrDefault() depending on your needs to get one specific answer or question.