在Objective C中调用方法的语法？

I come from the Java world, so to me it's all object.foo(), but in Objective C, is object messaging the only way to invoke a method?

我来自Java世界，所以对我而言，它都是object.foo（），但在Objective C中，对象消息传递是调用方法的唯一方法吗？

[object foo];

4 个解决方案

#1

The first thing that comes to mind is using @property and dot-notation. A class with @property named 'foo' allows you to do like this:

首先想到的是使用@property和dot-notation。 @property名为'foo'的类允许您这样做：

anInstance.foo = @"bar";

which literally translates at compile-time to

从字面上翻译成编译时

[anInstance setFoo:@"bar"];

(similar with "getters")

（与“getters”类似）

The other ways are more advanced, such as using NSObject's performSelector: method, or other systems such as NSInvocation, etc. Going deeper, there are ways to call methods in the runtime, with c functions (all of this syntax eventually boils down to calling c-functions anyway); but I'm sure that's not what you are after.

其他方式更高级，例如使用NSObject的performSelector：方法，或其他系统，如NSInvocation等。更深入，有一些方法可以在运行时调用方法，使用c函数（所有这些语法最终都归结为调用无论如何c函数）;但我确信那不是你追求的。

#2

You can use KVC:

你可以使用KVC：

 [label setValue:@"Some text" forKey:@"text"];

#3

Yes. You can use dot syntax to get or set Objective C properties. So for example setting text on a UILabel *label can be done either [label setText:@"some text"]; or label.text = @"some text";

是。您可以使用点语法来获取或设置Objective C属性。因此，例如，在UILabel *标签上设置文本可以[标签setText：@“some text”];或label.text = @“some text”;

#4

For pedantry's sake, why not get low-level:

为了迂腐，为什么不低级：

objc_msgSend(object, sel_getUid("foo"), errVar);

#1