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
