2013年09月15日

 虽然App Store能够提醒用户软件更新，但很多用户不会主动去更新一大堆的软件（我机器上待更新的软件在100个左右）。如果在软件开启时提醒用户更新 或者 更多中设置“检查更新”项，效果会好很多。

通常的做法是在自己的服务器上记录最新版本号，从iOS客户端请求，与本地版本号比较，不同则提示更新。这种做法简单，缺点是需要单独的服务器支持。

通过查阅相关文章，找到了如下方法，与上述方法类似，不过不需要另外的服务器支持。此为检查更新的最优方法。

NSString *version = @"";

NSURL *url = [NSURL URLWithString:@"http://itunes.apple.com/lookup?id=<Your app ID>"];

versionRequest = [ASIFormDataRequest requestWithURL:url];

[versionRequest setRequestMethod:@"GET"];

[versionRequest setDelegate:self];

[versionRequest setTimeOutSeconds:150];

[versionRequest addRequestHeader:@"Content-Type" value:@"application/json"];

[versionRequest startSynchronous];

//Response string of our REST call

NSString* jsonResponseString = [versionRequest responseString];

NSDictionary *loginAuthenticationResponse = [jsonResponseString objectFromJSONString];

NSArray *configData = [loginAuthenticationResponse valueForKey:@"results"];

for (id config in configData)

{

    version = [config valueForKey:@"version"];

}

//Check your version with the version in app store

if (![version isEqualToString:[itsUserDefaults objectForKey:@"version"]])

{

    ProAlertView *createUserResponseAlert = [[ProAlertView alloc] initWithTitle:@"New Version!!" message: @"A new version of app is available to download" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles: @"Download", nil];

    [createUserResponseAlert show];

    [createUserResponseAlert release];

}

- (void)alertView:(UIAlertView *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {

    // the user clicked one of the OK/Cancel buttons

    if (buttonIndex == 1)

    {

        NSString *iTunesLink = @"itms-apps://phobos.apple.com/WebObjects/MZStore.woa/wa/viewSoftwareUpdate?id=<appid>&mt=8";

        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:iTunesLink]];

    }

}