在ios开发中,object-c new和alloc/init的区别 ?


在 Objective-C 中,`new` 和 `alloc/init` 是用于创建对象的两种方法,但它们之间存在一些重要的区别。 1. `new`:在 Objective-C 中,`new` 是一个关键字,用于直接创建对象并自动调用 `init` 方法。这意味着,当你使用 `new` 创建一个对象时,该对象已经分配了内存并进行了初始化。需要注意的是,`new` 不会自动在栈上分配内存,因此创建的对象将通过 `autorelease` 加入到自动释放池中。 2. `alloc/init`:相比之下,`alloc` 和 `init` 是两个独立的函数。`alloc` 是用于在堆上为对象分配内存的函数,而 `init` 是用于初始化对象的函数。当你使用 `alloc/init` 创建一个对象时,你需要首先使用 `alloc` 为对象分配内存,然后调用对象的 `init` 方法进行初始化。与 `new` 不同,使用 `alloc/init` 创建的对象不会自动加入到自动释放池中。 起来,`new` 是一个方便的快捷方式,用于直接创建并初始化对象,而 `alloc/init` 则提供了更多的灵活性,允许你手动分配内存并初始化对象。使用 `new` 创建的对象会自动加入到自动释放池中,而使用 `alloc/init` 创建的对象则不会。 [2023-11-09 17:42:19 | AI写代码神器 | 298点数解答]
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