将日期转换为UTC格式

Question

我想以UTC格式转换本地日期。（美国格式）

Answer 1

-(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;
}

Answer 2

您应该设置NSTimeZone

NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:@"YYYY-MM-dd HH:mm:ss"];
[dateFormat setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
NSDate *date=[dateFormat dateFromString:[NSString stringWithFormat:@"%@",dateString]];
NSLog(@"Date %@",date);

Answer 3

Swift 4.2版本：

func dateAsString(inputDate: Date)->String
{
    let format = DateFormatter.init()
    format.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
    format.timeZone = TimeZone.init(identifier: "UTC")
    let str = format.string(from: inputDate)

    return str
}