我正在使用NSMutableArray。我想按日期获取值,就像在SQL group by "log_date" 中那样。
group by "log_date"
logMuArray ( "log_currenttime" = "4:30pm"; "log_date" = "11.12.2011"; "log_duration" = "1:30"; "log_currenttime" = "4:33pm"; "log_date" = "11.12.2011"; "log_duration" = "2:21"; "log_currenttime" = "4:40pm"; "log_date" = "11.12.2011"; "log_duration" = "5:30"; "log_currenttime" = "7:30pm"; "log_date" = "12.12.2011"; "log_duration" = "1:30"; "log_currenttime" = "7:33pm"; "log_date" = "12.12.2011"; "log_duration" = "2:21"; "log_currenttime" = "7:40pm"; "log_date" = "12.12.2011"; "log_duration" = "5:30"; "log_currenttime" = "07:16pm"; "log_date" = "19.12.2011"; "log_duration" = "0:07"; "log_currenttime" = "7:31pm"; "log_date" = "19.12.2011"; "log_duration" = "0:04"; "log_currenttime" = "7:33pm"; "log_date" = "19.12.2011"; "log_duration" = "0:03"; "log_currenttime" = "7:33pm"; "log_date" = "19.12.2011"; "log_duration" = "0:06"; "log_currenttime" = "7:35pm"; "log_date" = "19.12.2011"; "log_duration" = "0:05"; )
**所以,我刚刚表演了.
NSLog(@"logMuArray %@",[logMuArray valueForKey:@"log_date"]);
但是我只想获取唯一的日期。**我考虑过NSPredicate或可变集等等。
logMuArray ( "11.12.2011", "11.12.2011", "11.12.2011", "12.12.2011", "12.12.2011", "12.12.2011",