iOS 动态添加方法

+ (BOOL)resolveInstanceMethod:(SEL)sel {
    //如果是test方法 打印日志
    if (sel == @selector(test)) {
        NSLog(@"resolveInstanceMethod");
        //动态添加test方法
        class_addMethod(self, @selector(test), testIMP, "v@:");
        return YES;
    }else {
        return [super resolveInstanceMethod:sel];
    }
}
void testIMP (void) {
    NSLog(@"test invoke");
}