通过NSURL获取网络标准时间

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
    NSURL *url=[NSURL URLWithString:@"http://www.baidu.com"];
    NSURLRequest *request=[NSURLRequest requestWithURL:url];
    NSURLConnection *connection=[[NSURLConnection alloc]initWithRequest:request delegate:self startImmediately:YES];
    [connection start];
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
    NSLog(@"response%@",response);
    NSHTTPURLResponse *httpResponse=(NSHTTPURLResponse *)response;
    if ([response respondsToSelector:@selector(allHeaderFields)]) {
        NSDictionary *dic=[httpResponse allHeaderFields];
        NSLog(@"dic:%@",dic);
        NSString *time=[dic objectForKey:@"Date"];
        NSString *time1=[time substringFromIndex:16];
        NSString *time2=[time1 substringToIndex:9];
        NSArray*array=[time2 componentsSeparatedByString:@":"];
        int hour=[[array objectAtIndex:0] intValue];
        int minute=[[array objectAtIndex:1] intValue];
        NSString *now=[NSString stringWithFormat:@"%0.2d:%0.2d",hour+8,minute];
        NSLog(@"date:%@",now);
    }
}