iPad Dev: Turn a given Date or String from SQL into NSDate

I have an app that creates and stores a session with a given start date. The user would create a new work session and when they start it, the current time would get saved to the database. The app needs to count time between the start and end of a work session. However, I need to be able to pause, restart, and continue sessions, so I need to get the date from the database.

Say a user starts at 10:30am on a particular day and continues their work session until 12:30pm. Say they need to close the app for whatever reason and come back to the work session. The session needs to count and show the current elapsed time since the be开发者_开发问答ginning. So, I wanted to make an NSDate object with the start time taken from the database...but I can't. At least, I can't find a way of initializing a Date object with a string or even a set of parameters. I'm sure there's a way to do it, but I can't find one.

Take a look at the dateFromString: method on NSDateFormatter

you can start with the Apple Doc here

http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/DataFormatting/Articles/dfDateFormatting10_4.html#//apple_ref/doc/uid/TP40002369-SW1

could type up examples, but I think the documentation contains some