Swift计算属性和存储属性的重要区别
发布时间：2020-12-14 06:16:32 所属栏目：百科 来源：网络整理
导读：As the preceding example demonstrates,a computed instance property function can refer to other instance properties; it can also call instance methods. This is important,because in general the initializer for a stored property can do neithe
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As the preceding example demonstrates,a computed instance property function can refer to other instance properties; it can also call instance methods. This is important,because in general the initializer for a stored property can do neither of those things. The reason this is legal for a computed property is that its functions won’t be called until the instance actually exists. 像前面例子示意的那样,一个计算实例属性函数可以引用其它实例属性;它同样可以调用实例方法. 这是非常重要的,因为一般的存储属性的初始化器既不能调用实例方法也不能引用实例变量.而计算属性做这些事合法的原因是它的方法在实例变量实际存在前不会调用. （编辑：李大同） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |