Date Comparison

[StefanL]

Hi Folks,

I need to compare some dates and put them in an "if - else" statement:

I have the "NOW Date", the "Give Date" and then I have "Given Date MINUS 10 Minutes". Now I should compare whether NOW Date is "smaller" then "Given Date minus 10 Minutes", and if YES then an action should be started:

 NSDate *myDate = [NSDate date];
NSDate *aktDate = [Date from DB];
NSDate *tenMinutes = [aktDate dateByAddingTimeInterval:-60*10];

This is my result so far - I have no clue how I can get NOW > [Given Date MINUS 10 Minutes]

Thanks a lot for your help and advice!

BR,

Stefan

[apatsufas]

NSDate has an compare method. You need something like this

if([myDate compare: aktDate]==NSOrderedAscending){ //if myDate is earlier then aktDate
    //Do something
}
else if([myDate compare: aktDate]==NSOrderedDescending){ //if myDate is later then aktDate
    //Do something
}
else{ 
//Do something else
}

[Duncan C]

Originally Posted by StefanL

Hi Folks,

I need to compare some dates and put them in an "if - else" statement:

I have the "NOW Date", the "Give Date" and then I have "Given Date MINUS 10 Minutes". Now I should compare whether NOW Date is "smaller" then "Given Date minus 10 Minutes", and if YES then an action should be started:

 NSDate *myDate = [NSDate date];
NSDate *aktDate = [Date from DB];
NSDate *tenMinutes = [aktDate dateByAddingTimeInterval:-60*10];

This is my result so far - I have no clue how I can get NOW > [Given Date MINUS 10 Minutes]

Thanks a lot for your help and advice!

BR,

Stefan

You can certainly work with NSDate objects, and create a new date for "given minus 10 minutes".

I prefer working with the NSDate methods that return a floating point number that represents the date:

[NSDate timeIntervalSinceReferenceDate]

returns a floating point value that's the number of seconds passed since January 1, 2001.

You can save your start date as a time interval, then get the date at the the end time, and do simple floating point math on the two dates to calculate the number of seconds between them.

I like those methods because you can use them without having to create date objects and worry about retaining/releasing them..

There are also methods like

- (NSTimeInterval)timeIntervalSinceReferenceDate

That give you the NSTimeInterval value for an existing date, timeIntervalSinceNow, etc.