Question

I’m reading data from a XML file which has a UTC date looking like “2011-05-04T00:00:00”, and a UTC epoch looking like 1352716800.

Parsing the UTC epoch to NSDate would probably be much safer than messing around with a complex date format. How would I parse the UTC epoch to NSDate? With NSDateFormatter and a special format for “UTC Epoch”?

I think that it is [[NSDate alloc] initWithTimeIntervalSince1970:epoch] and a test seemed to work. But I am not sure if that’s just correct by accident or if the “UTC epoch” is “Since 1970”. The Apple Docs don’t mention UTC Epoch.

Answer 1

YES, you are correct it is UTC Epoch. For Reference if “Epoch time is UTC” checkout this

NSString *epochTime = @"1352716800";

// (Step 1) Convert epoch time to SECONDS since 1970
NSTimeInterval seconds = [epochTime doubleValue];
NSLog (@"Epoch time %@ equates to %qi seconds since 1970", epochTime, (long long) seconds);

// (Step 2) Create NSDate object
NSDate *epochNSDate = [[NSDate alloc] initWithTimeIntervalSince1970:seconds];
NSLog (@"Epoch time %@ equates to UTC %@", epochTime, epochNSDate);