IOS類執行個體方法調用

一、respondsToSelector : SEL 和 performSelector :  withObject 帶一個參數

二、如果需要帶多參數，可以對多參數用字典封裝使用

三、如果確實需要巨集指令引數可以參考Three20擴充NSInvocation用法，可以多參數和傳回值

- (id)performSelector:(SEL)selector withObject:(id)p1 withObject:(id)p2 withObject:(id)p3 {  NSMethodSignature *sig = [self methodSignatureForSelector:selector];  if (sig) {    NSInvocation* invo = [NSInvocation invocationWithMethodSignature:sig];    [invo setTarget:self];    [invo setSelector:selector];    [invo setArgument:&p1 atIndex:2];    [invo setArgument:&p2 atIndex:3];    [invo setArgument:&p3 atIndex:4];    [invo invoke];    if (sig.methodReturnLength) {      id anObject;      [invo getReturnValue:&anObject];      return anObject;    } else {      return nil;    }  } else {    return nil;  }}