Objective-C setting NSDate to current UTC
Is there an easy way to ini开发者_StackOverflow社区t an NSDate
with the current UTC date/time?
[NSDate date];
You may want to create a category that does something like this:
-(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;
}
NSDate is a reference to an interval from an absolute reference date, January 1, 2001 00:00 GMT. So the class method [NSDate date] will return a representation of that interval. To present that data in a textual format in UTC, just use the NSDateFormatter with the appropriate NSTimeZone (UTC) to render as needed.
NSDate objects encapsulate a single point in time, independent of any particular calendrical system or time zone. Date objects are immutable, representing an invariant time interval relative to an absolute reference date (00:00:00 UTC on 1 January 2001).
Swift version:
extension NSDate {
func getUTCFormateDate() -> String {
let dateFormatter = NSDateFormatter()
let timeZone = NSTimeZone(name: "UTC")
dateFormatter.timeZone = timeZone
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
return dateFormatter.stringFromDate(self)
}
}
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