I have Data In List It is the employee’s entry and exit information.
Datetime User_id UserName Tna
--------------------------------------------------------------------------------
2022-03-15 08:30:23 01 John null
2022-03-15 09:43:40 01 John null
2022-03-15 10:16:52 01 John null
2022-03-15 13:45:23 01 John null
2022-03-15 15:38:23 01 John null
2022-03-15 17:36:23 01 John null
2022-03-15 08:31:23 02 Eva null
2022-03-15 10:16:52 02 Eva null
2022-03-15 13:45:23 02 Eva null
2022-03-15 15:38:23 02 Eva null
2022-03-15 17:30:23 02 Eva null
Information in List retrieved from API.
I would like to know how to filter the items in the list. First check-in and last check-out
by filtering by time , How to get output like this using LINQ?
Datetime User_id UserName Tna
--------------------------------------------------------------------------------
2022-03-15 08:30:23 01 John IN
2022-03-15 17:36:23 01 John OUT
2022-03-15 08:31:23 02 Eva IN
2022-03-15 17:30:23 02 Eva OUT
>Solution :
You may want group by person, then select first and last of each group.
Assumption
Every person has at least one in and out entry.
pseudocode
var result = lst.GroupBy(x => x.User_id)
.Select(g => g.OrderBy(x => x.Datetime))
.Select(g => new[] { g.First() }.Concat(new[] { g.Last() }));