Do NSDate's in CoreData encapsulate time zone?

I keep dates and times in my CoreData store and need to accurately present to users the time as originally entered. The problem is that if they entered 4:00 on the East Coast, then later look at the recorded time on the West Coast, it appears as 1:00, since the iPhone translates universal times to local times. I need it to show 4:00 -- probably 4:00 (+3h00).

Before I go and restructure my Core Data model, I want to be sure there's no way to derive the NSTimeZone that was active at creation-time from a stored NSDate object. Is there? If not, any recommendation how best to capture NSTimeZone at creati开发者_如何转开发on time myself? An NSNumber representing the creation-time NSTimeZone time difference from GMT?

Thanks.

As you've discovered, NSDate represents a universal point in time and does not include specific time zone information.

I'd suggest instead of storing the offset, store the NSTimeZone's name property. Then you can use +[NSTimeZone timeZoneWithName:] to get the time zone and thence convert it to local time. This gives you maximum flexibility in how you display the information to the user.