如何从NSDate iOS获取UTC时间

Question

我想在我的iOS应用中记录服务器时间，我正在使用NHNetworkTime库获取网络时间，当我尝试打印以下显示GMT的代码时，通过选择UTC，如何在UTC中打印日期时间？

NSDate* datetime = [NSDate networkDate];
    NSDateFormatter* dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]]; // Prevent adjustment to user's local time zone.
    [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss.SSS Z z "];
    NSString* dateTimeInIsoFormatForZuluTimeZone = [dateFormatter stringFromDate:datetime];

NSLog(@"%@",dateTimeInIsoFormatForZuluTimeZone);

this is printing 2016-03-09 06:51:23.406 +0000 GMT 

Answer 1

协调世界时（UTC）和格林威治标准时间（GMT）之间没有时差。 您可以从这里获取更多信息更多信息

Answer 2

参考：-

-(NSString *)getUTCFormateDate:(NSDate *)localDate
{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    NSTimeZone *timeZone = [NSTimeZone timeZoneWithName:@"UTC"];
    [dateFormatter setTimeZone:timeZone];
    [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
    NSString *dateString = [dateFormatter stringFromDate:localDate];
    [dateFormatter release];
    return dateString;
}

而且要有时间

-(NSString *)getTimeFromDate:(NSDate *)localDate
{
    NSDateFormatter *dateFormatter = [[[NSDateFormatter     alloc]init]autorelease];
    dateFormatter.dateFormat = @"MM/dd/yy";

    NSString *dateString = [dateFormatter stringFromDate: localDate];

    NSDateFormatter *timeFormatter = [[[NSDateFormatter alloc]init]autorelease];
    timeFormatter.dateFormat = @"HH:mm:ss";
    return [timeFormatter stringFromDate: localDate];
}