YZHookHandler 是什么？
YZHookHandler 是 iOS 上的一个轻量级 AOP 库。它利用 method swizzling 技术为已有的类或者实例方法添加额外的代码，大部分源码代码来自ReactiveObjC ，作者在这个基础上做了二次开发，以便更方便的去使用。
怎么使用 YZHookHandler
- (YZHookHandler *)yz_hookForSelector:(SEL)selector;
- (YZHookHandler *)yz_hookForSelector:(SEL)selector fromProtocol:(Protocol *)protocol;
使用上述两个方法得到YZHookHandler，在YZHookHandler内有三个方法：
/// Called after the original implementation
- (YZHookHandler *)after:(YZHookArgsBlock)after;
/// Will replace the original implementation.
- (YZHookHandler *)instead:(YZHookArgsBlock)instead;
/// Called before the original implementation.
- (YZHookHandler *)befor:(YZHookArgsBlock)befor;
///Remove the current hook.
- (void)removeHook;
YZHookArgsBlock是一个block，在成功hook后将响应带回对应的参数。
其中dealloc是不允许被hook的。
///Hook selector alias prefix, default is yz_alias.
@property (class, nonatomic, copy) NSString *yz_hookHandlerForSelectorAliasPrefix;
///Swizzle subclass suffix, default is _YZHookHandler.
@property (class, nonatomic, copy) NSString *yz_subclassSuffix;
另外你可以自定义方法的前缀和子类化对象的前缀
简单的使用
YZTest *test1 = [YZTest new];
__weak YZTest *weakTest1 = test1;
[[[weakTest1 yz_hookForSelector:@selector(test)] after:^(NSArray * _Nonnull args) {
NSLog(@"after %@",weakTest1);
}] befor:^(NSArray * _Nonnull args) {
NSLog(@"befor %@",weakTest1);
}] ;
[test1 test];
NSObject.yz_subclassSuffix = @"_test";
NSObject.yz_hookHandlerForSelectorAliasPrefix = @"test_";
YZTest *test2 = [YZTest new];
[[test2 yz_hookForSelector:@selector(test)] after:^(NSArray * _Nonnull args) {
}];
[test2 test];
总结
