Sorting DateTime property

Question

User2074931137 posted

The sort below on DateTime property is incorrect (order by or order by descending does not seem to be working).

Any ideas on what I might be doing wrong would be greatly appreciated.

        [DataType(DataType.Time)]
        [Column(TypeName = "DateTime2")]
        [DisplayFormat(DataFormatString = "{0:hh:mm}", ApplyFormatInEditMode = true)]
        [Display(Name = "AM Report")]
        public DateTime? ContactReportAM { get; set; }

                switch (sortOrder)
                {
                    default:
                        assignments = assignments.OrderBy(s => s.Contact.ContactReportAM);
                        break;

                    case "reportam_desc":
                        assignments = assignments.OrderByDescending(s => s.Contact.ContactReportAM);
                        break;

http://fvm.azurewebsites.net/Assignment/ContactReportAM   (default sort)

AM Report	Employee	Vehicle	Down	Route
	Dan D.	2186		I
06:28	Millie			821
04:00	Robert M.			827
05:45	David			23 / 119
05:50	Richard T.	2220		DD
06:01	Robert G.			49 / 145
06:04	Dan K.	2386		34
06:05	Bob B.	2218 DVR		K
06:06	Ana	2224		JJ
06:06	Walter			818
06:07	Robert S.
06:07	Tom	2211		32
06:08	Georgiana			816
06:11	Felix			828
06:12	Teresa			829
06:12	Jill	2385		J
06:17	Steve			817
06:19	Arthur	2183		U
06:20	Irene
06:21	Marie P.			830
06:22	Cynthia			815
06:22	Gary G.			48 / 144
06:23	Ralph F.			826
06:23	Rosemary			820
06:25	Bob G.	2186		I
06:27	Richard G.	2182		Y
06:29	AJ	2219 DVR		T
06:29	Duvert	2388		V
06:29	Roman	2239		D
06:29	Peter			824
06:29	Roman
06:31	Lennard	2234		P
06:31	Joe L.	2389		L
06:31	Dan B.	2223		N
06:32	Sandy	2229		O
06:32	Lewis			819
06:34	Jean (GiGi)	2244		S
06:34	Bill	2250		M
06:34	Ray C.	2387		X
06:34	Ralph A.			813
06:37	Ed			28 / 124
06:39	Mike			809
06:39	Dan T.			812
06:49	Emily			808
06:59	Sal L.			R
07:00	Ray S.			814
07:15	Jean			810
07:55	Lorna			811
06:23	Bob W.			823
06:32	Anthony			Tech

http://fvm.azurewebsites.net/Assignment/ContactReportAM?sortOrder=reportam_desc

AM Report	Employee	Vehicle	Down	Route
06:32	Anthony			Tech
06:23	Bob W.			823
07:55	Lorna			811
07:15	Jean			810
07:00	Ray S.			814
06:59	Sal L.			R
06:49	Emily			808
06:39	Dan T.			812
06:39	Mike			809
06:37	Ed			28 / 124
06:34	Ralph A.			813
06:34	Bill	2250		M
06:34	Jean (GiGi)	2244		S
06:34	Ray C.	2387		X
06:32	Lewis			819
06:32	Sandy	2229		O
06:31	Lennard	2234		P
06:31	Joe L.	2389		L
06:31	Dan B.	2223		N
06:29	AJ	2219 DVR		T
06:29	Duvert	2388		V
06:29	Roman	2239		D
06:29	Peter			824
06:29	Roman
06:27	Richard G.	2182		Y
06:25	Bob G.	2186		I
06:23	Ralph F.			826
06:23	Rosemary			820
06:22	Cynthia			815
06:22	Gary G.			48 / 144
06:21	Marie P.			830
06:20	Irene
06:19	Arthur	2183		U
06:17	Steve			817
06:12	Jill	2385		J
06:12	Teresa			829
06:11	Felix			828
06:08	Georgiana			816
06:07	Tom	2211		32
06:07	Robert S.
06:06	Ana	2224		JJ
06:06	Walter			818
06:05	Bob B.	2218 DVR		K
06:04	Dan K.	2386		34
06:01	Robert G.			49 / 145
05:50	Richard T.	2220		DD
05:45	David			23 / 119
04:00	Robert M.			827
06:28	Millie			821
	Dan D.	2186		I

Answer 1

User475983607 posted

My best guess the report spans more than one day and therefore the sort is working as expected.

Answer 2

User2074931137 posted

https://forums.asp.net/p/2153881/6255132.aspx?p=True&t=636883309140915404

Answer 3

User1520731567 posted

Hi 3v3rhart,

It seems that OrderByDescending or OrderBy can not be accurate to the time(hh mm ss).

You could refer to this link:

https://stackoverflow.com/a/31650314

It isn't pretty at all, but it get's the job done.

Or I suggest you could refer to this link:

using the Date and TimeOfDay properties for the sort:

https://stackoverflow.com/questions/5464783/linq-to-sql-order-by-datetime-desc-then-order-by-the-time-part-of-the-data-asc

.OrderByDescending(c=> c.Time.Date).ThenBy(c=> c.Time.TimeOfDay);

or change the other way to achieve the goal:

https://stackoverflow.com/questions/1433088/asp-net-mvc-model-orderby-date-has-no-effect

.OrderByDescending(a => a.Date).ThenBy(a => a.Id).ToList();

Hope my reply will be helpful to you.

Best Regards.

Yuki Tao