方法一：

//获取网络当前时间

- (NSDate *)getInternetDate {

NSString *urlString = @"http://m.baidu.com";

urlString = [urlString stringByAddingPercentEscapesUsingEncoding: NSUTF8StringEncoding];

// 实例化NSMutableURLRequest，并进行参数配置

NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];

[request setURL:[NSURL URLWithString: urlString]];

[request setCachePolicy:NSURLRequestReloadIgnoringCacheData];

[request setTimeoutInterval: 2];

[request setHTTPShouldHandleCookies:FALSE];

[request setHTTPMethod:@"GET"];

NSHTTPURLResponse *response;

[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:nil];

// 处理返回的数据

//NSLog(@"response is %@",response);

NSString *date = [[response allHeaderFields] objectForKey:@"Date"];

date = [date substringFromIndex:5];

date = [date substringToIndex:[date length]-4];

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];

formatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US"];

[formatter setDateFormat:@"dd MMM yyyy HH:mm:ss"];

NSDate *netDate = [[formatter dateFromString:date] dateByAddingTimeInterval:60*60*8];

return netDate;

}

方法二：

NSURL *url=[NSURL URLWithString:@"http://m.baidu.com"];

NSURLRequest *request=[NSURLRequest requestWithURL:url];

NSURLConnection *connection=[[NSURLConnection alloc]initWithRequest:request delegate:self startImmediately:YES];

[connection start];

}

/**

*  代理方法

*/

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{

//      NSLog(@"response--%@",response);

NSHTTPURLResponse *httpResponse=(NSHTTPURLResponse *)response;

if ([response respondsToSelector:@selector(allHeaderFields)]) {

NSDictionary *dict=[httpResponse allHeaderFields];

//      NSLog(@"dict--%@",dict);

NSString *date=[dict objectForKey:@"Date"];

NSLog(@"date--%@___class---%@",date,[date class]);

}}