自iOS6.0后获取通讯录列表需要询问用户，经过用户同意后才可以获取通讯录用户列表。而且ABAddressBookRef的初始化工作也由ABAddressBookCreate函数转变为ABAddressBookCreateWithOptions函数。下面代码是兼容之前版本的获取通讯录用户列表方法。

ABAddressBookRef addressBook = nil;if ([[UIDevice currentDevice].systemVersion floatValue] >= 6.0) {     addressBook = ABAddressBookCreateWithOptions(NULL, NULL);     //等待同意后向下执行     dispatch_semaphore_t sema = dispatch_semaphore_create(0);     ABAddressBookRequestAccessWithCompletion(addressBook, ^(bool granted, CFErrorRef error)     {         dispatch_semaphore_signal(sema);     });              dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);     dispatch_release(sema); } else {     addressBook = ABAddressBookCreate(); } NSArray *personArray = (NSArray *)ABAddressBookCopyArrayOfAllPeople(addressBook);