如何确定NSObject是否具有某些属性? [英] how can you find out if an NSObject has a certain property?

问题描述

比方说，在Apple API版本1.0中，存在一个类NSFoo，其属性为颜色". API 1.1添加了属性大小".

Let's say in Apple API version 1.0, there is a class NSFoo with a property 'color'. API 1.1 adds property 'size'.

我想知道是否可以使用getter:myFoo.size

I want to know whether I can use the getter: myFoo.size

[myFoo responsesToSelector:@selector(getSize)]不能按预期工作.

[myFoo respondsToSelector:@selector(getSize)] doesn't work as expected.

找出对象是否具有属性的正确方法是什么?谢谢！

What's the correct way to find out if an object has a property? Thanks!

推荐答案

您已经关闭.您的选择器应该正是您要发送给对象的消息:

You're close. Your selector should be exactly the message you want to send to the object:

if ( [myFoo respondsToSelector:@selector(size)] ) {
    int size = [myFoo size]; // or myFoo.size in dot-notation.
    // ...
}

应该工作.

这篇关于如何确定NSObject是否具有某些属性?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！