NSPredicate for time interval

问题

I have one table with 4 fields startdate ,enddate, starttime and endtime. I need to set predicate something like

if
   startdate<= currentdate and currentdate <= enddate
   if 
      starttime <= currenttime and endtime <= endtime
   else
      starttime <= currenttime and currenttime<= 23.00 or 0.00 <= currentime and currentime <= endtime   

How i set predicate for this type of condition.Current date and current time is the my system time in gmt.

回答1:

You can use NSCompoundPredicate

Create NSMutableArray to hold your predicates with their conditions

NSMutableArray *conditions = [NSMutableArray array];

Build your conditions and add them to this array

[conditions addObject:[NSPredicate predicateWithFormat:@"startdate <= %@ AND enddate <= %@",[NSDate date],[NSDate date]]];

Add as many conditions as you like. Finally build your NSCompoundPredicate

NSPredicate *predicate = [NSCompoundPredicate andPredicateWithSubpredicates:conditions];

If you have your startdate and enddate in NSDate format you can access it time component as well, there is no need of separate starttime and endtime just compare the two dates and should be ok.

来源：https://stackoverflow.com/questions/23802117/nspredicate-for-time-interval