compare two identical lists of strings

Question

Let's say I have following code:

    List<string> numbers = new List<string> { "1", "2" };
    List<string> numbers2 = new List<string> { "1", "2"};

    if (numbers.Equals(numbers2))
    {

    }

Like you can see I have two lists with identical items. Is there a way to check if these two lists are equal by using one method?

SOLUTION:

Use SequenceEqual()

Thanks

See http://stackoverflow.com/questions/1546925/comparing-two-liststring-for-equality — dash, Dec 14 '11 at 16:31
@Ozkan what if you had duplicates? like `numbers: { 1, 1, 2}` and `numbers2: { 1, 2 }` would you consider those equal? — Matthew Cox, Dec 14 '11 at 16:34
@Matthew Cox, Hi, this is not considered to occur. But I found the method its `SequenceEqual()` — Ozkan, Dec 14 '11 at 16:36
If all you want to do is "compare two identical lists of strings", then `return true` will do the job. It's also the fastest solution — jalf, Dec 14 '11 at 16:40
possible duplicate of [Is there a built-in method to compare collections in C#?](http://stackoverflow.com/questions/43500/is-there-a-built-in-method-to-compare-collections-in-c) — nawfal, Nov 08 '13 at 23:06

score 4 · Accepted Answer · answered Dec 14 '11 at 16:38

4

Use Enumerable.SequenceEqual, but Sort the lists first.

answered Dec 14 '11 at 16:38

kol

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score 2 · Answer 2 · answered Dec 14 '11 at 16:34

2

// if order does not matter
bool theSame = numbers.Except(numbers2).Count() == 0;

// if order is matter
var set = new HashSet<string>(numbers);
set.SymmetricExceptWith(numbers2);
bool theSame = set.Count == 0;

answered Dec 14 '11 at 16:34

sll

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2

That would be my answer. Just depends on if duplicates matter. If they do then this would return a false positive. – Matthew Cox Dec 14 '11 at 16:35

compare two identical lists of strings

2 Answers2