iPhone开发札记（18）将Http Header中的Date转换成NSDate_Iphone

iPhone开发笔记（18）将Http Header中的Date转换成NSDate

1、获取Http Header

我这里是在AppDelegate中定义了一个ASIDownloadCache的全局变量myCache

AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];NSDictionary *dic = [appDelegate.myCache cachedResponseHeadersForURL:[NSURL URLWithString:@"http://....../getPictureNews.aspx"]];

输出dic，得到如下的结果：

{    "Cache-Control" = private;    "Content-Length" = 2404;    "Content-Type" = "text/html;charset=utf-8";    Date = "Sun, 07 Oct 2012 06:13:41 GMT";    Server = "Microsoft-IIS/6.0";    "X-ASIHTTPRequest-Fetch-date" = "Sun, 07 Oct 2012 06:13:44 GMT";    "X-AspNet-Version" = "2.0.50727";    "X-Powered-By" = "ASP.NET";}

2、获取Date并转化

NSString *lastUpdate = [dic objectForKey:@"Date"];NSDateFormatter *formatter = [[NSDateFormatter alloc] init];[formatter setDateFormat:@"EEE',' dd' 'MMM' 'yyyy HH':'mm':'ss zzz"];NSDate *date = [formatter dateFromString:lastUpdate];NSLog(@"%@",date);

输出date的结果为

2012-10-07 06:13:44 +0000

3、总结

关键是在NSDateFormatter的formatter String要写正确，最后得到date之后就可以做其他的事情了，进行其他日期操作就没什么区别了。