事件用字串來呼叫

#include <objc/message.h>

- (IBAction)buttonevent:(id)sender {

NSDictionary *itemDic = [[NSDictionary alloc]init];

  SEL s = NSSelectorFromString(@"eventname:");

        if ([self respondsToSelector:s]) {

            ((id (*)(id, SEL, NSDictionary*))objc_msgSend)(self, s, itemDic);

        }

}

- (void) eventname:(id)obj

{

    //do something...

}