为什么在声明变量时CGSize不使用*? [英] Why CGSize doesn't use * when declaring variables?

问题描述

当我创建一个名为Sprite的类的实例时，我会做类似的事情:

When I create an instance of a class called, say, Sprite, I do something like:

Sprite *mySprite = [[Sprite alloc]init];

但是为什么在创建CGSize或int类型变量时不能使用*?基本上，*是做什么用的?

But why when creating a CGSize or int type variable, I can't use *? Basically, what's the * for?

推荐答案

*表示指针. CGSize被声明为struct，而Sprite是一个类，并且在Objective-C中，所有类均由指针引用.

The * denotes a pointer. CGSize is declared as a struct and Sprite is a class, and in Objective-C all classes are referenced by a pointer.

您可以在

You can find additional information in the Programming with Objective-C documentation. The relevant sections are Use Pointers to Keep Track of Objects and Methods Can Return Values.

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