OC + RAC(七) RACSubject和RACSignal的区别

-(void)_test8{ /// RACSubject继承自RACSignal 可是RACSubject和RACSignal的区别？
    //1能接收1，2 //可是2只能接收2
    RACSubject *subject = [RACSubject subject]; [subject subscribeNext:^(id x) { NSLog(@"订阅者1%@", x); }]; [subject sendNext:@"subject1"]; [subject subscribeNext:^(id x) { NSLog(@"订阅者2%@", x); }]; [subject sendNext:@"subject2"]; }