Question

 NSDate *newDate=[newDate dateByAddingTimeInterval:difference];

Now I want to convert this newDate to NStimeInterval.

How can I do this conversion?

Answer 1

NDDate and NSTimeInterval are two diferent things, you cannot convert a NSDate to a NSTimeInterval and vice-versa.

NSDate represents an absolute date and NSTimeInterval represents the time between two dates.

However you can create a NSTimeInterval from a reference date with this method:

- (NSTimeInterval)timeIntervalSinceDate:(NSDate *)anotherDate

You can do it like this:

NSDate *referenceDate = /* Your reference date */
NSDate *date = /* Your date */
NSTimeInterval timeInterval = [date timeIntervalSinceDate:referenceDate];