ios runtime swizzle

ios runtime swizzle

#import 

@implementation NSObject(Extension)+ (void)swizzleClassMethod:(Class)class originSelector:(SEL)originSelector otherSelector:(SEL)otherSelector{    Method otherMehtod = class_getClassMethod(class, otherSelector);    Method originMehtod = class_getClassMethod(class, originSelector);    // 交換2個方法的實現    method_exchangeImplementations(otherMehtod, originMehtod);}+ (void)swizzleInstanceMethod:(Class)class originSelector:(SEL)originSelector otherSelector:(SEL)otherSelector{    Method otherMehtod = class_getInstanceMethod(class, otherSelector);    Method originMehtod = class_getInstanceMethod(class, originSelector);    // 交換2個方法的實現    method_exchangeImplementations(otherMehtod, originMehtod);}@end@implementation NSArray(Extension)+ (void)load{    [self swizzleInstanceMethod:NSClassFromString(@"__NSArrayI") originSelector:@selector(objectAtIndex:) otherSelector:@selector(hm_objectAtIndex:)];}- (id)hm_objectAtIndex:(NSUInteger)index{    if (index < self.count) {        return [self hm_objectAtIndex:index];    } else {        return nil;    }}@end@implementation NSMutableArray(Extension)+ (void)load{    [self swizzleInstanceMethod:NSClassFromString(@"__NSArrayM") originSelector:@selector(addObject:) otherSelector:@selector(hm_addObject:)];    [self swizzleInstanceMethod:NSClassFromString(@"__NSArrayM") originSelector:@selector(objectAtIndex:) otherSelector:@selector(hm_objectAtIndex:)];}- (void)hm_addObject:(id)object{    if (object != nil) {        [self hm_addObject:object];    }}- (id)hm_objectAtIndex:(NSUInteger)index{    if (index < self.count) {        return [self hm_objectAtIndex:index];    } else {        return nil;    }}@end