Runtime 实现方法替换

直接上代码

首先引入runtime头文件

#import

+(void)load

{

static dispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

Class class = [self class];

swizzleMethod(class, @selector(touchbutton1:), @selector(touchbutton2:));

});

}

- (void)viewDidLoad {

[super viewDidLoad];

UIButton *button5 = [[UIButton alloc]initWithFrame:CGRectMake(220, 200, 100, 100)];

[button5 setTitle:@"4" forState:UIControlStateNormal];

button5.backgroundColor = [UIColor grayColor];

[button5 addTarget:self action:@selector(touchbutton1:) forControlEvents:UIControlEventTouchUpInside];

button5.tag = 5;

[button5 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];

[self.view addSubview:button5];

}

void swizzleMethod(Class class,SEL originalSelector,SEL swizzledSelector){

Method originalMethod = class_getInstanceMethod(class, originalSelector);

Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector);

BOOL didAddMethod = class_addMethod(class, originalSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod));

if (didAddMethod) {

class_replaceMethod(class, swizzledSelector, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod));

}else {

method_exchangeImplementations(originalMethod, swizzledMethod);

}

}

-(void)touchbutton1:(UIButton *)sender

{

NSLog(@"******* 点击 11111********");

}

-(void)touchbutton2:(UIButton *)sender

{

NSLog(@"******* 点击 222222********");

}

这样就实现了 点击调用的button1方法 变为调用button2 方法啦