Searching in ListArray C#

Question

What is the fastest method for searching data from list array in C#?

My code:

public class fruits
{
    public string Initial;
    public string Fruit;
    public fruits(string initials, string names)
    {
        Initial = initials;
        Fruit = names;
    }
}

// load
List<fruits> List = new List<fruits>();

List.Add(new fruits("A", "Apple"));
List.Add(new fruits("P", "Pineapple"));
List.Add(new fruits("AP", "Apple Pineapple"));


//combo box select text
var text = combobox.SelectText();
for (int i=0; i<list.Count(); i++)
{
    if (list[i].Fruit == text)
    {
        MessageBox.Show(list[i].Initial);
    }
}

I know this search method is not good, if list data contains too much data.

What do you mean with "fastest" ? : Fast do develop or fast if you run the code? — Fruchtzwerg, Nov 27 '16 at 11:33
@Fruchtzwerg Fastest ≙ fastest running; Easiest ≙ fastest to code. — devRicher, Nov 27 '16 at 11:45
if `Initial` is unique among fruits ; it could be better to use a `Dictionary` — Sehnsucht, Nov 27 '16 at 19:59

score 2 · Accepted Answer · edited May 23 '17 at 12:24

2

If you want a "fast" solution, you should use a foreach instead of LINQ. This solution can improve your perfomance a lot:

fruits firstOrDefault = null:
foreach (fruits f in List)
{
    if (f.Fruit == text)
    {
        FirstOrDefault = f;
        break;
    }
}

You can get few more information about the LINQ performance in posts like

edited May 23 '17 at 12:24

Community

1
1

answered Nov 27 '16 at 12:04

Fruchtzwerg

10,999
12
40
49

Thanks for a **fast** solution. ;) – devRicher Nov 27 '16 at 12:07
@devRicher - thanks for the "fast" and "easy" hint :-) – Fruchtzwerg Nov 27 '16 at 12:09
Thanks for a fast solution. ;) – marshall Nov 27 '16 at 12:23

score 1 · Answer 2 · answered Nov 27 '16 at 11:32

1

You can use linq

 var result = List.FirstOrDefault(q => q.Fruit == text );
 MessageBox.Show(result.Initial);

answered Nov 27 '16 at 11:32

Sajeetharan

216,225
63
350
396

1

Why is the answer description "You can use linq" when the question is tagged [linq]? – devRicher Nov 27 '16 at 12:06
because I know what it linq from another forum. haha – marshall Nov 27 '16 at 12:22
@marshall Even though it is not the fastest, it is another answer for your question – Sajeetharan Nov 27 '16 at 13:13

score 0 · Answer 3 · answered Nov 27 '16 at 17:09

The best (and only) way to tell what method is fastest for a certain situation is to actually benchmark/measure it with different algorithms. You already have two answers/approaches here (LINQ and foreach). Time both of them and then pick the faster one.

Or in other words: Measuring your code gives you an advantage over those people who think they are too smart to measure. ;)

To speed things up further you might want to consider to keep the list sorted and then do a binary search on the list. It increases the time for insertion, because you have to sort the list after inserts, but it should speed up the search process. But then again: Do not just take my word for it, measure it!

Searching in ListArray C#

3 Answers3