CODEWITHSUNDEEP
c#.net-2.0
Brad
Brad

Reputation: 21160

how do i return a count of match items

I have a sorted generic list. I would like to return the first 10 that match a condition.

sort of like the method below but only the first 10 items

  mySortedlist.FindAll(delegate(myclass tmp){ return tmp.ID == 123;});

Upvotes: 1

Views: 137

Answers (2)

Chad
Chad

Reputation: 19609

Something like the following:

int count = 0;
mySortedlist.FindAll(delegate(myclass tmp){ return (tmp.ID == 123 && ++count <= 10);});

Upvotes: 8

Jon Skeet
Jon Skeet

Reputation: 1499770

Well, that will return a list already. You can create your own equivalent of Enumerable.Take pretty easily:

public static IEnumerable<T> Take<T>(IEnumerable<T> source, int size)
{
    int count = 0;
    foreach (T item in source)
    {
        yield return item;
        count++;
        if (count == size)
        {
            yield break;
        }
    }
}

Then you can use:

List<myclass> filtered =  mySortedlist.FindAll(delagate(myclass tmp) {
     return tmp.ID == 123;
});
List<myclass> list = new List<myclass>(Helper.Take(filtered, 10));

Another option is to use LINQBridge so that you can use LINQ as much as possible - ideally using C# 3 even when you're targeting .NET 2.0, if possible. It'll make your life much simpler :)

Upvotes: 6

Related Questions