#import "ViewController.h"

@interface ViewController ()
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.title = @"版本檢測更新";
    self.view.backgroundColor = [UIColor whiteColor];
    [self checkVersion];   //檢測升級  
}

-(void)checkVersion
{
    NSString *newVersion;
    NSURL 
 
*url = [NSURL URLWithString:@"http://itunes.apple.com/cn/lookup?id=1139094792"];//這個URL地址是該app在iTunes connect裡面的相關配置資訊。其中id是該app在app store唯一的ID編號。
    NSString *jsonResponseString = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:nil];
    NSLog(@"通過appStore獲取的資料資訊：%@",jsonResponseString);
    
    NSData 
 
*data = [jsonResponseString dataUsingEncoding:NSUTF8StringEncoding];
//    解析json資料
    id json = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
    NSArray *array = json[@"results"];
    for (NSDictionary *dic in array) {
        newVersion = [dic valueForKey:@"
 
version"];
    }
    
    NSLog(@"通過appStore獲取的版本號是：%@",newVersion);
    //獲取本地軟體的版本號
    NSString *localVersion = [[[NSBundle mainBundle]infoDictionary] objectForKey:@"CFBundleVersion"];
    NSString *msg = [NSString stringWithFormat:@"你當前的版本是V%@，發現新版本V%@，是否下載新版本？",localVersion,newVersion];
    //對比發現的新版本和本地的版本
    if ([newVersion floatValue] > [localVersion floatValue])
    {
        UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"升級提示"message:msg preferredStyle:UIAlertControllerStyleAlert]; 
        [self presentViewController:alert animated:YES completion:nil];
       
        [alert addAction:[UIAlertAction actionWithTitle:@"現在升級" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"https://itunes.apple.com/cn/app/yi-ka-tongbic-ban/id1139094792?l=en&mt=8"]];這裡寫的URL地址是該app在app store裡面的下載連結地址，其中ID是該app在app store對應的唯一的ID編號。
            NSLog(@"點選現在升級按鈕");
        }]];
        
        [alert addAction:[UIAlertAction actionWithTitle:@"下次再說" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            NSLog(@"點選下次再說按鈕");
        }]];
    }
}