Objective-C响应方法

 响应方法
    响应方法

    [对象 performSelector:(SEL)];

#import <Foundation/Foundation.h>

//动物类
@interface Animal : NSObject
{ 
}
-(void)run;
@end

@implementation Animal 
-(void)run{
  NSLog(@"动物在跑！");
}
@end

//狗类
@interface Dog : NSObject 
{ 
}
-(void)run;
-(void)eat;
-(void)eat:(NSString*)_foodName;
-(void)eat:(NSString*)_foodName andDogName :(NSString*)_dogName;
@end

@implementation Dog
-(void)run{
  NSLog(@"狗在跑！");
}
-(void)eat{
  NSLog(@"狗在吃");
}
-(void)eat:(NSString*)_foodName{
  NSLog(@"狗在吃：%@", _foodName);
}
-(void)eat:(NSString*)_foodName andDogName :(NSString*)_dogName{
  NSLog(@"这是%@狗，吃的食物是:%@",_dogName,_foodName);
}
@end 

//以下是动态类型检测
int main(int argc,const char * argv[]){
 
  Animal *animal = [Dog new]; 
  SEL s1 = @selector(eat);
  if([animal responseToSelector:s1]){
    //这个performSelector就是响应方法  是无参的方法
    [animal performSelector:s1];
  }
   
  SEL s2 = @selector(eat:);
  if([animal respondsToSelector:s2]){
    //这个是响应有参数的方法
    //不能这么写，因为要传一个参数
    //[animal performSelector:s2];
    
    [animal performSelector:s2 withObject:@"有参数的响应方法"];
  }
  
  SEL s3 = @select(eat:andDogName:);
  if([animal respondsToSelector:s3]){
    //以下是响应一个方法，传递两个参数
    [animal performSelector:s3 withObject:@"参数1" withObject:@"参数2"];
  }
   
  return 0;
}