List Custom Sort

Question

I have a list of items which need to be sorted in a very particular way.

Take this example:

public class PayStubDetailItem
{ 
    public string Code { get; set; }
}

void Main()
{
    var bonus = new PayStubDetailItem() { Code = "Bonus" };
    var ot = new PayStubDetailItem() { Code = "OT"};
    var reg = new PayStubDetailItem() { Code = "Reg"};
    var otPrem = new PayStubDetailItem() { Code = "OTPrem"};
    var tps = new PayStubDetailItem() { Code = "3ps"};

    var list = new List<PayStubDetailItem> {
        bonus, ot, reg, otPrem, tps
    };
}

My requirement states that sorting should be as follows: Reg, OT, OTPrem, Alpha-sort by code.

Explained in words, if list contains 'Reg' code it should come first, if it also contains 'OT' it should come after Reg, etc.. All items which codes are different from those specific three should be alphabetically sorted.

In my example the sorted list should look like this: Reg, OT, OTPrem, 3ps, Bonus

What would be the most elegant way to accomplish that? Perhaps, using LINQ or a custom comparer.

This is what I have attempted so far but it's to verbose:

var subList = list.Where(i => i.Code != "OT" && i.Code != "Reg" && i.Code != "OTPrem");
subList = subList.OrderBy(l => l.Code);
var newList = new List<PayStubDetailItem>();
if (list.Select(c => c.Code).Contains("Reg"))
{
    newList.Add(list.Where(i => i.Code == "Reg").FirstOrDefault());
}
if (list.Select(c => c.Code).Contains("OT"))
{
    newList.Add(list.Where(i => i.Code == "OT").FirstOrDefault());
}
if (list.Select(c => c.Code).Contains("OTPrem"))
{
    newList.Add(list.Where(i => i.Code == "OTPrem").FirstOrDefault());
}
newList.AddRange(subList);
newList.Dump();

Thanks

@DavidL I have updated my post with my current attempt but I don't like it. It's ugly — Adolfo Perez
– Adolfo Perez, Commented Sep 8, 2016 at 21:26

Ivan Stoev · Accepted Answer · 2016-09-08 21:35:17Z

1

You can use Linq like this:

var result = list.
    .OrderBy(c => c.Code == "Reg" ? 0 : c.Code == "OT" ? 1 : c.Code == "OTPrem" ? 2 : 3)
    .ThenBy(c => c.Code)
    .ToList();

The OrderBy expression will give you the required priority order, while the ThenBy will do the alphabetical part.

answered Sep 8, 2016 at 21:35

Ivan Stoev

208k17 gold badges356 silver badges376 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Adolfo Perez Over a year ago

This is what I meant by elegant!l Thanks so much @IvanStoev

Scott Perham · Accepted Answer · 2016-09-08 21:24:30Z

0

As your sorting logic is quite unique to your problem, I would suggest an implementation the IComparer(T) interface and then calling Sort(IComparer(T)) on your list.

class MyComparer : IComparer<PayStubDetailItem>
{
    public int Compare(PayStubDetailItem x, PayStubDetailItem y)
    {
        //Your implementation
    }
}

answered Sep 8, 2016 at 21:24

Scott Perham

2,4901 gold badge14 silver badges21 bronze badges

Collectives™ on Stack Overflow

List Custom Sort

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related