CODEWITHSUNDEEP
c#linq
user222427
user222427

Reputation:

Linq, select List Item where column is the max value

I basically have a List that has a few columns in it. All I want to do is select whichever List item has the highest int in a column called Counted.

List<PinUp> pinned= new List<PinUp>();

class PinUp
{
    internal string pn { get; set; }
    internal int pi{ get; set; }
    internal int Counted { get; set; }
    internal int pp{ get; set; }
}

So basically I just want pinned[whichever int has highested Count]

Hope this makes sense

The problem is i want to remove this [whichever int has highested Count] from the current list. So I have to no which int it is in the array

Upvotes: 1

Views: 2884

Answers (5)

fodien
fodien

Reputation: 23

Try the following:

PinUp pin = pinned.OrderByDescending(x => x.Counted).First();

Upvotes: 1

James
James

Reputation: 82096

var excludingHighest = pinned.OrderByDescending(x => x.Counted)
                             .Skip(1);

If you need need to have a copy of the one being removed and still need to remove it you can do something like

var highestPinned = pinned.OrderByDescending(x => x.Counted).Take(1);
var excludingHighest = pinned.Except(highestPinned);

Upvotes: 2

Tim Schmelter
Tim Schmelter

Reputation: 460108

One way, order by it:

PinUp highest = pinned
    .OrderByDescending(p => p.Counted)
    .First();

This returns only one even if there are multiple with the highest Counted. So another way is to use Enumerable.GroupBy:

IEnumerable<PinUp> highestGroup = pinned
    .GroupBy(p => p.Counted)
    .OrderByDescending(g => g.Key)
    .First();

If you instead just want to get the highest Counted(i doubt that), you just have to use Enumerable.Max: 

int maxCounted = pinned.Max(p => p.Counted);

Update:

The problem is i want to remove this [whichever int has highested Count] from the current list.

Then you can use List(T).RemoveAll:

int maxCounted = pinned.Max(p => p.Counted);
pinned.RemoveAll(p => p.Counted == maxCounted);

Upvotes: 3

user2160375
user2160375

Reputation:

You can order it:

var pin = pinned.OrderByDescending(p => p.Counted).FirstOrDefault();
// if pin == null then no elements found - probably empty.

If you want to remove, you don't need an index:

pinned.Remove(pin);

Upvotes: 1

esskar
esskar

Reputation: 10940

it is a sorting problem. Sort your list by Counted in descending order and pick the first item. Linq has a way to do it:

var highest = pinned.OrderByDescending(p => p.Counted).FirstOrDefault();

Upvotes: 1

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