Question

核心数据中的所有对象

{
    dtStartDate = "Jun 10, 2016-10:40 AM";
},
{
    dtStartDate = "May 12, 2016-06:55 AM";
},
{
    dtStartDate = "May 12, 2016-08:05 AM";
},
{
    dtStartDate = "May 12, 2016-02:30 PM";
},
{
    dtStartDate = "Jun 12, 2016-07:50 AM";
},
{
    dtStartDate = "Jul 12, 2016-08:50 AM";
},
{
    dtStartDate = "Jun 12, 2016-07:50 AM";
},
{
    dtStartDate = "May 12, 2016-10:00 AM";
},
{
    dtStartDate = "Jun 12, 2016-07:30 AM";
}

我使用这种日期格式来预测核心数据

NSDate *dt = [NSDate date];
NSDateFormatter *df =[[NSDateFormatter alloc] init];
[df setDateFormat:@"MMM dd, yyyy-hh:mm a"];
NSString *today =[df stringFromDate:dt];
NSDate *dateOfToday = [df dateFromString:today];
NSMutableArray *meetings=nil;

现在我有两个条件获取未来日期（包括当前）和过去的获取日期

获取未来日期（包括今天）

  NSPredicate *predicate = [NSPredicate predicateWithFormat:@"dtStartDate >=  %@",dateOfToday];
   NSMutableArray *meetingsArr = [[CoreDataAPI sharedInstance] checkForRecordExistInTable:@"Tbl_Meeting" withCompountPredicate:[NSArray arrayWithObjects:predicate, nil]];

返回9个对象（全部） 的 WRONG

   NSPredicate *predicate = [NSPredicate predicateWithFormat:@"dtStartDate <= %@",dateOfToday];

   NSMutableArray *meetingsArr = [[CoreDataAPI sharedInstance] checkForRecordExistInTable:@"Tbl_Meeting" withCompountPredicate:[NSArray arrayWithObjects:predicate, nil]];

返回0对象（无） 的 WRONG

请先帮助我解决它

我可以使用此方法手动完成并正常工作。但我只想做谓词

-(NSMutableArray *)filterMeetingsBasedOnTime:(BOOL)isPastMtng :(NSMutableArray*)arr
{
NSDate *dt = [NSDate date];
NSDateFormatter *df =[[NSDateFormatter alloc] init];
[df setDateFormat:@"MMM dd, yyyy-hh:mm a"];


NSMutableArray *arrMeeting = [[NSMutableArray alloc] init];

for(NSDictionary *sMtngDict in arr)
{
    NSDate  *meetDate = [df dateFromString:[sMtngDict valueForKey:@"dtStartDate"]];

    if(isPastMtng)
    {
        if([meetDate timeIntervalSinceDate:dt]<0)
        {
            [arrMeeting addObject:sMtngDict];
        }
    }
    else{
        if([meetDate timeIntervalSinceDate:dt]>=0)
        {
            [arrMeeting addObject:sMtngDict];
        }
    }
}

return arrMeeting;
}

我们可以在谓词中使用此方法逻辑，如果是，那么如何？

日期谓词不起作用

0 个答案: