应用版本检测更新

- (void)checkUpdateVersion {
    
    //1 获取当前项目版本号：
    //[self toast:@"当前已经是最新版本"];
    NSDictionary *infoDic=[[NSBundle mainBundle] infoDictionary];
    NSString *currentVersion=infoDic[@"CFBundleShortVersionString"];//currentVersion为当前工程项目版本号
    
    //2 联网检测项目在AppStore上的版本号
    NSString *storeAppID = @"AppStore上的版本号";//配置自己项目在商店的ID
    NSError *error;
    NSData *response = [NSURLConnection sendSynchronousRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"http://itunes.apple.com/cn/lookup?id=%@",storeAppID]]] returningResponse:nil error:nil];
    if (response == nil) {
        NSLog(@"你可能没有连接网络哦");
        return;
    }
    NSDictionary *appInfoDic = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&error];
    if (error) {
        NSLog(@"hsUpdateAppError:%@",error);
        return;
    }
    NSLog(@"可输出一下看看%@",appInfoDic);
    
    NSArray *array = appInfoDic[@"results"];
    
    if (array.count < 1) {
        NSLog(@"此APPID为未上架的APP或者查询不到");
        return;
    }
    NSDictionary *dic = array[0];
    //商店版本号
    NSString *appStoreVersion = dic[@"version"];
    
    //3 比较版本号，跳转到手机自带的AppStore项目页面供用户下载：
    
    NSLog(@"当前版本号:%@\n商店版本号:%@",currentVersion,appStoreVersion);
    //设置版本号，主要是为了区分不同的版本，比如有1.2.1、1.2、1.31各种类型
    currentVersion = [currentVersion stringByReplacingOccurrencesOfString:@"." withString:@""];
    if (currentVersion.length==2) {
        currentVersion  = [currentVersion stringByAppendingString:@"0"];
    }else if (currentVersion.length==1){
        currentVersion  = [currentVersion stringByAppendingString:@"00"];
    }
    appStoreVersion = [appStoreVersion stringByReplacingOccurrencesOfString:@"." withString:@""];
    if (appStoreVersion.length==2) {
        appStoreVersion  = [appStoreVersion stringByAppendingString:@"0"];
    }else if (appStoreVersion.length==1){
        appStoreVersion  = [appStoreVersion stringByAppendingString:@"00"];
    }
    
    //4当前版本号小于商店版本号,就更新
    if([currentVersion floatValue] < [appStoreVersion floatValue])
    {
        UIAlertController *alercConteoller = [UIAlertController alertControllerWithTitle:@"版本有更新" message:[NSString stringWithFormat:@"检测到新版本(%@),是否更新?",dic[@"version"]] preferredStyle:UIAlertControllerStyleAlert];
        UIAlertAction *actionYes = [UIAlertAction actionWithTitle:@"更新" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            
            //应用下载链接
            NSString *downloadURLStr = dic[@"trackViewUrl"];
            
            //此处加入应用在app store的地址，方便用户去更新，一种实现方式如下
            NSURL *url = [NSURL URLWithString:downloadURLStr];
            [[UIApplication sharedApplication] openURL:url];
            
            NSLog(@"url  %@", url);
        }];
        UIAlertAction *actionNo = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
            
        }];
        [alercConteoller addAction:actionYes];
        [alercConteoller addAction:actionNo];
        
        
        [self presentViewController:alercConteoller animated:YES completion:^{
                    }];
    }else{
        NSLog(@"检测到不需要更新");
    }
}