使用冒号:或不与选择器一起使用 [英] Use colon : or not with selectors

问题描述

我想知道:写没有冒号@selector(mySelector)或没有冒号@selector(mySelector:)的选择器名称有什么区别?

I was wondering: what's the difference between writing a selector name with no colon @selector(mySelector), or @selector(mySelector:) with the colon?

如:

UIBarButtonItem *addButton = [[UIBarButtonItem alloc]initWith... 
                                                       target:self
                                                       action:@selector(addAction:)];

没有冒号我找不到另一个例子，但是我很确定我已经看过其中一些.

I can't find another example without the colon, but I'm quite sure I have already seen some of them.

推荐答案

方法名称为且仅当使用参数时，才需要冒号.

The colon is needed after the method's name if and only if the method takes an argument.

没有功能参数:

-(void)addAction {}

// Use ...@selector(addAction)...

有参数:

-(void)addAction:(id)info {}

// Use ...@selector(addAction:)...

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