ios 使用ASIHTTPRequest来检查版本更新

 - (void) alertWithTitle: (NSString *)_title_  msg:(NSString *)msg delegate:(id)_delegate cancelButtonTitle:(NSString*)_cancelTitle otherButtonTitles:(NSString*)_otherTitles{
     UIAlertView *alert = [[UIAlertView alloc] initWithTitle:_title_
                                                     message:msg
                                                    delegate:_delegate
                                           cancelButtonTitle:_cancelTitle
                                           otherButtonTitles:_otherTitles,nil];
     [alert show];
 }

 #pragma mark - update
 -(void)checkUpdate{
     MBKAppDelegate *mbkApp = (MBKAppDelegate *)[[UIApplication sharedApplication] delegate];
     if (![mbkApp networkIsReach]) {
         return;
     }

     NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://itunes.apple.com/lookup?id=%@",kAppId]];
     ASIHTTPRequest *request =[ASIHTTPRequest requestWithURL:url];
     [request setDelegate:self];
     [request setDidFinishSelector:@selector(requestDone:)];
     [request setDidFailSelector:@selector(requestWentWrong:)];
     [request startSynchronous];
 }

 #pragma mark - asihttprequest
 - (void)requestDone:(ASIHTTPRequest *)request
 {
     NSError *err = nil;
     NSDictionary *dictionary =
     [[CJSONDeserializer deserializer] deserializeAsDictionary:[request responseData] error:&err];
     if (err != nil) {
         [self failure];
         return;
     }
     NSArray *a = [dictionary objectForKey:@"results"];
     if (a.count == ) {
         [self failure];
         return;
     }
     NSDictionary *d = [a objectAtIndex:];
     NSString *newVersion = [d objectForKey:@"version"];
     NSDictionary *infoDict = [[NSBundle mainBundle] infoDictionary];
     NSString *nowVersion = [infoDict objectForKey:@"CFBundleVersion"];
     NSString *msg = @"";
     NSString *cancelTitle = @"";
     NSString *otherTitles = @"";
     if(![nowVersion isEqualToString:newVersion])
     {
         msg = @"版本有更新";
         cancelTitle = @"取消";
         otherTitles = @"更新";
     }else{
         msg = @"已经是最新版本啦";
         cancelTitle = @"好";
         otherTitles = nil;
     }
     [self alertWithTitle:nil msg:msg delegate:self cancelButtonTitle:cancelTitle otherButtonTitles:otherTitles];
 }

 - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
     if(buttonIndex==){
         NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"https://itunes.apple.com/us/app/qun-xiang-dao/id%@?ls=1&mt=8",kAppId]];
         [[UIApplication sharedApplication]openURL:url];
     }
 }

 - (void)requestWentWrong:(ASIHTTPRequest *)request
 {
     [self failure];
 }

 - (void)failure{
     [self alertWithTitle:nil msg:@"检查失败了" delegate:self cancelButtonTitle:@"好" otherButtonTitles:nil];
 }

转：http://my.oschina.net/brucezcq/blog/148905