objective-c - 如何在ios中将数据存储在NSCache中？

Question

我对 NSCache 很陌生。

我有一个 API 调用会产生多个对象。如何将这些对象存储在 NSCache 中，这样我就不需要再次调用 API。

NSCache 可以存储多少数据。NSCache 中存储数据是否有特定的限制。

请帮帮我。

Answer 1

看看documentation和 sample code .

An NSCache object is a collection-like container, or cache, that stores key-value pairs, similar to the NSDictionary class.

Here是 Nick Zitzmann 很好的解释。

NSCache is similar to NSMutableDictionary, with the differences being:
1. It is guaranteed to be thread-safe.
2. It is much slower to access.
3. It may throw out objects from time to time. You can set costs and limits, but they're not guaranteed to be followed.
4. It is not toll-free bridged to anything in CoreFoundation.
5. You can't query the number of objects that are in the cache.
6. You can't enumerate a cache.

I can only recommend using NSCache to store objects you wouldn't care about if they were arbitrarily destroyed. If the objects must not be destroyed, or if access speed is an issue, then use NSMutableDictionary instead.