我同情这个问题——我也发现(发现?)这个选择令人困惑，所以我开始科学地看看哪个数据结构是最快的(我用VB做了测试，但我想c#会是一样的，因为这两种语言在CLR级别上做同样的事情)。您可以在这里看到我进行的一些基准测试结果(还有一些关于在哪种情况下使用哪种数据类型最好的讨论)。

如果可能的话，使用泛型。这包括:

List而不是ArrayList 字典而不是哈希表

哈希表/字典是O(1)性能，这意味着性能不是大小的函数。知道这一点很重要。

编辑:在实践中，哈希表/字典<>查找的平均时间复杂度是O(1)。

我能想到的是:

Array* - represents an old-school memory array - kind of like a alias for a normal type[] array. Can enumerate. Can't grow automatically. I would assume very fast insert and retrival speed. ArrayList - automatically growing array. Adds more overhead. Can enum., probably slower than a normal array but still pretty fast. These are used a lot in .NET List - one of my favs - can be used with generics, so you can have a strongly typed array, e.g. List<string>. Other than that, acts very much like ArrayList Hashtable - plain old hashtable. O(1) to O(n) worst case. Can enumerate the value and keys properties, and do key/val pairs Dictionary - same as above only strongly typed via generics, such as Dictionary<string, string> SortedList - a sorted generic list. Slowed on insertion since it has to figure out where to put things. Can enum., probably the same on retrieval since it doesn't have to resort, but deletion will be slower than a plain old list.

我倾向于一直使用List和Dictionary——一旦开始使用带有泛型的强类型，就很难再回到标准的非泛型了。

还有很多其他的数据结构，比如KeyValuePair，你可以用它做一些有趣的事情，还有SortedDictionary，它也很有用。

泛型集合将比非泛型集合执行得更好，特别是在遍历许多项时。这是因为装箱和开箱不再发生。

它们在智能感知上拼得很好。只需输入System.Collections。或者System.Collections.Generics(首选)，你会得到一个可用的列表和简短描述。