长时间不用，竟然写不出来了，之前的一个项目里的用户信息单例，现在看来当初理解的很透测，记下来，方便随时复习。

//  QYUserSingleton.m

//  Hallyu

//

//  Created by XJW on 14-9-29.

//  Copyright (c) 2014年 qingyun. All rights reserved.

//

#import "QYUserSingleton.h"

@implementation QYUserSingleton

static QYUserSingleton *userIn;

+ (id) allocWithZone:(struct_NSZone *)zone

{

    staticQYUserSingleton *userIn;//静态指针，

    staticdispatch_once_t once ;

    //NSLog(@"%ld",once);

    dispatch_once(&once, ^{

       // userIn = [[QYUserSingleton alloc] init];

        userIn = [superallocWithZone:zone];

    });

    return userIn;

}

+ (QYUserSingleton *)sharedUserSingleton

{

    if (!userIn) {

        userIn = [[QYUserSingletonalloc]init];

    }

    returnuserIn;

}

- (id)init

{

    self = [superinit];

    if (self) {

        [selfinitWithAccount:@""andPhone:@""andTestNum:@"" andPasscode:@""andUserId:@""andNickName:@""andfavouriyesCount:@""andFollowersCount:@""andIsLogin:NOandIcon_url:@"" ];

    }

    returnself;

}

- (void)initWithAccount:(NSString *)account

               andPhone:(NSString *)phone

             andTestNum:(NSString *)testNum

            andPasscode:(NSString *)passcode

              andUserId:(NSString *)userId

            andNickName:(NSString *)nickName

     andfavouriyesCount:(NSString *)favCount

      andFollowersCount:(NSString *)followersCount

             andIsLogin:(BOOL)isLogin

            andIcon_url:(NSString *)iconUrl

{

    _phoneNum = [[NSStringalloc]initWithString:phone];

    _testNum = [[NSStringalloc]initWithString:testNum];

    _account = [[NSStringalloc]initWithString:account];

    _passcode = [[NSStringalloc]initWithString:passcode];

    _user_id = [[NSStringalloc]initWithString:userId];

    _nickName = [[NSStringalloc]initWithString:nickName];

    _favourites_count = [[NSStringalloc]initWithString:favCount];

    _follwers_count = [[NSStringalloc]initWithString:followersCount];

}

- (id)copy

{

    returnself;

}

@end

单例demo