LINQ provides a few different methods that return you a single object: Single(), First(), and Take(1).It took me a while, but I think I understand the difference: Single() operates on a collection of exactly one object and simply returns the object. First() operates on a collection of any number of objects and returns the first object. Take(1) operates on a collection of any number of objects and returns a collection containing the first object....
Linq提供了一些不同的返回单个对象的函数：Single(),First()和Take(1)。
Single():操作一个集合，同时强要求只有一个对象匹配，并返回这一个。
First():操作一个集合，可以有多个对象匹配，但是只返回第一个。
Take(1):操作一个集合，可以有对个对象匹配，单只返回第一个，但是这里返回的是一个集合，而不是单个的概念。