问题：
in the System.Linq namespace, we can now extend our IEnumerable 's to have the Any() and Count() extension methods . 在System.Linq命名空间中，我们现在可以将IEnumerable扩展为具有Any()和Count() 扩展方法 。
I was told recently that if i want to check that a collection contains 1 or more items inside it, I should use the .Any() extension method instead of the .Count() > 0 extension method because the .Count() extension method has to iterate through all the items. 最近，我被告知，如果我要检查一个集合包含在它里面1个或多个项目，我应该使用.Any()而不是扩展方法.Count() > 0扩展方法，因为.Count()扩展方法必须遍历所有项目。
Secondly, some collections have a property (not an extension method) that is Count or Length . 其次，某些集合具有Count或Length 属性 （不是扩展方法）。 Would it be better to use those, instead of .Any() or .Count() ? 它会更好利用这些，而不是.Any()或.Count()
yea / nae ? 是/否？
解决方案：
参考一： https://stackoom.com/question/1HMq/哪种方法效果更好-Any-与-Count-gt参考二： https://oldbug.net/q/1HMq/Which-method-performs-better-Any-vs-Count-0
来源：oschina
链接：https://my.oschina.net/stackoom/blog/4283401