定义的鲜明特性是，它会返回一个无序集合（ 文档）。

The defined behavior of Distinct is that it will return an unordered collection (Documentation).

不过目前执行的Linq中清晰到的对象将维持秩序。这并不能保证其他LINQ提供程序，虽然和行为不应依赖该等资料。

However the current implementation of Distinct in Linq to Objects will preserve order. This is not guaranteed for other LINQ providers though and the behavior should not be relied upon.