#closure

Shall we always use [unowned self] inside closure in Swift

Published at November 21, 2019 ·  1 min read

在什么情况下使用 unowned self 和 weak self,weak 是一个 Optional 类型,意味着,需要判断其值是否为 nil,而 unowned 如果值为 nil 则会 crash 整个程序。”The difference between unowned and weak is that weak is declared as an Optional while unowned is not. By declaring it weak you get to handle the case that it might be nil inside the closure at some point. If you try to access an unowned variable that happens to be nil, it will crash the whole program....


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