iOS设备检查更新版本：

#pragma mark - 检查更新- (void)checkUpdateWithAPPID:(NSString *)APPID{    //获取当前应用版本号    NSDictionary *appInfo = [[NSBundle mainBundle] infoDictionary];        NSString *currentVersion = [appInfo objectForKey:@"CFBundleVersion"];        NSString *updateUrlString = [NSString stringWithFormat:@"http://itunes.apple.com/lookup?id=%@",APPID];    NSURL *updateUrl = [NSURL URLWithString:updateUrlString];    versionRequest = [ASIFormDataRequest requestWithURL:updateUrl];    [versionRequest setRequestMethod:@"GET"];    [versionRequest setTimeOutSeconds:60];    [versionRequest addRequestHeader:@"Content-Type" value:@"application/json"];        //loading view    CustomAlertView *checkingAlertView = [[CustomAlertView alloc] initWithFrame:NAVIGATION_FRAME style:CustomAlertViewStyleDefault noticeText:@"正在检查更新..."];    checkingAlertView.userInteractionEnabled = YES;    [self.navigationController.view addSubview:checkingAlertView];    [checkingAlertView release];        [versionRequest setCompletionBlock:^{                [checkingAlertView removeFromSuperview];                NSError *error = nil;        NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:[versionRequest responseData] options:NSJSONReadingMutableContainers error:&error];        if (!error) {            if (dict != nil) {                //            DLog(@"dict %@",dict);                int resultCount = [[dict objectForKey:@"resultCount"] integerValue];                if (resultCount == 1) {                    NSArray *resultArray = [dict objectForKey:@"results"];                    //                DLog(@"version %@",[resultArray objectAtIndex:0]);                    NSDictionary *resultDict = [resultArray objectAtIndex:0];                    //                DLog(@"version is %@",[resultDict objectForKey:@"version"]);                    NSString *newVersion = [resultDict objectForKey:@"version"];                                        if ([newVersion doubleValue] > [currentVersion doubleValue]) {                        NSString *msg = [NSString stringWithFormat:@"最新版本为%@,是否更新？",newVersion];                        newVersionURlString = [[resultDict objectForKey:@"trackViewUrl"] copy];                        DLog(@"newVersionUrl is %@",newVersionURlString);                        //                    if ([newVersionURlString hasPrefix:@"https"]) {                        //                         [newVersionURlString replaceCharactersInRange:NSMakeRange(0, 5) withString:@"itms-apps"];                        //                    }                        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"提示" message:msg delegate:self cancelButtonTitle:@"暂不" otherButtonTitles:@"立即更新", nil];                        alertView.tag = 1000;                        [alertView show];                        [alertView release];                    }else                    {                        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"提示" message:@"您使用的是最新版本！" delegate:self cancelButtonTitle:nil otherButtonTitles:@"确定", nil];                        alertView.tag = 1001;                        [alertView show];                        [alertView release];                    }                }            }        }else        {            DLog("error is %@",[error debugDescription]);        }    }];        [versionRequest setFailedBlock:^{        [checkingAlertView removeFromSuperview];                CustomAlertView *alertView = [[CustomAlertView alloc] initWithFrame:NAVIGATION_FRAME style:CustomAlertViewStyleWarning noticeText:@"操作失败，请稍候再试！"];        [self.navigationController.view addSubview:alertView];        [alertView release];        [alertView selfRemoveFromSuperviewAfterSeconds:1.0];    }];        [versionRequest startSynchronous];  }- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{    DLog(@"newVersionUrl  is %@",newVersionURlString);    if (buttonIndex) {        if (alertView.tag == 1000) {            if(newVersionURlString)            {                [[UIApplication sharedApplication] openURL:[NSURL URLWithString:newVersionURlString]];            }        }    }}

 

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