NSArray 之 SEL 的保存

简介

最近在初始化类的时候，会有很多没有返回值的初始化方法需要调用，每次都需要再写一遍，所以想把函数装进 NSArray 中可以自动调用。结果查了一下真的可以，所以做个笔记记一下

- (void)viewDidLoad {
    [super viewDidLoad];
    NSString* A = NSStringFromSelector(@selector(loadA));
    NSString* B = NSStringFromSelector(@selector(loadB));
    NSString* C = NSStringFromSelector(@selector(loadC));
    NSArray *arr = @[A,B,C];
    [arr enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        NSString *selector = obj;
        if (!self) { return; }
        SEL performSelector = NSSelectorFromString(selector);
        if ([self respondsToSelector:performSelector]){
            [self performSelector:performSelector];
        }
    }];
}

- (void)loadA{
    NSLog(@"call load A +++++++");
}

- (void)loadB{
    NSLog(@"call load B ++++++++");
}

- (void)loadC{
    NSLog(@"call load C +++++");
}   

然后就写了一个小 demo,写完后报了警告，查过爆栈热门 iOS 问题后，解决了这个问题。

image.png

    NSString* A = NSStringFromSelector(@selector(loadA));
    NSString* B = NSStringFromSelector(@selector(loadB));
    NSString* C = NSStringFromSelector(@selector(loadC));
    NSArray *arr = @[A,B,C];
    [arr enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        NSString *selector = obj;
        if (!self) { return; }
        SEL performSelector = NSSelectorFromString(selector);
        IMP imp = [self methodForSelector:performSelector];
        void (*func)(id, SEL) = (void *)imp;
        func(self, performSelector);
    }];