Making a cast in List.Sort

Question

So I am having a list with objects. Those objects have a property TimeStamp. The problem is, this property is a string. Now when sorting the list by TimeStamp, the sort function ignores "AM" and "PM"

var historicalAlarms = new List<IHistoricalAlarmItem>();
foreach(...)
{ 
    ... 
}

historicalAlarms.Sort((x, y) => ((Belimed.Alarm.HistoricalAlarmItem)x).TimeStamp.CompareTo(((Belimed.Alarm.HistoricalAlarmItem)y).TimeStamp));

Is it possible to convert the TimeStamp to a new DateTime object to make the Sort function not ignore AM and PM? Remember that the objects in the List also need to be cast to another type (unfortunately they have the same name)

This works:

historicalAlarms.Sort((x, y) => ((Belimed.Alarm.HistoricalAlarmItem)x).ActivationTime.CompareTo(((Belimed.Alarm.HistoricalAlarmItem)y).ActivationTime));

This doesnt:

historicalAlarms.OrderBy(x => DateTime.Parse((Belimed.Alarm.HistoricalAlarmItem)x.TimeStamp))

Yes, you should convert the strings to DateTimes and compare them. — Derek, Jul 10 '17 at 12:12
_"The problem is, this property is a string"_ A fault confessed is half redressed. — Tim Schmelter, Jul 10 '17 at 12:18

NtFreX · Answer 1 · 2017-07-10T12:15:32.643

2

You can use OrderBy and DateTime.Parse to achieve that.

historicalAlarms = historicalAlarms
    .OrderBy(value => DateTime.Parse(value.TimeStamp))
    .ToList();

edited Jul 10 '17 at 12:15

answered Jul 10 '17 at 12:12

NtFreX

10,379
2
43
63

3

And assign it back to the original variable. `OrderBy` doesn't modify the original list, `Sort` does. – Manfred Radlwimmer Jul 10 '17 at 12:13
Good, might need: historicalAlarms = historicalAlarms.OrderBy(value => DateTime.Parse(value.TimeStamp)).ToList(); – Derek Jul 10 '17 at 12:13
I think you need a .ToList() on the end? – Derek Jul 10 '17 at 12:15
I have updated my question. There is still a problem – user2877820 Jul 10 '17 at 12:49
@user2877820 Don't forget that `OrderBy` doesn't change the list but returns a new one. You need to assign the return type back to the list. – NtFreX Jul 10 '17 at 12:52

Making a cast in List.Sort

1 Answers1