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C# determine if list of strings have same value without regard to position

I have two list of strings I am getting from a function. How can I tell if they are identical without respect to the order.

meaning

list1 = {"a", "b", "c"}
list2 = {"c", "b", "a"}
list3 = {"a")

list1 and list2 would be equal
list1 and list3 would not be equal
list2 and list3 would not be equal

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ste5an

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kaufmed

If you cannot use LINQ (for whatever reason), then the "old school" approach would be to sort the lists and then compare each element:

bool areEqual = true;

list1.Sort();
list2.Sort();

if (list1.Length != list2.Length)
{
    areEqual = false;
}
else
{
    for (int i = 0; i < list1.Length; i++)
    {
        if (list1[i] != list2[i])
        {
            areEqual = false;
        }
    }
}

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it_saige

Normally I would say that Enumerable.SequenceEqual would suffice, but in this case (since the items are out of order) it would not. So you would sort the items before comparing:

Enumerable.SequenceEqual(list1.OrderBy(i => i), list2.OrderBy(i => i))

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For custom types, you will have to implement a comparer if the standard comparer does not work. In those cases, code would be changed to:

Enumerable.SequenceEqual(list1.OrderBy(i => i, myListComparer), list2.OrderBy(i => i, myListComparer))

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More information on implementing a comparer:

http://msdn.microsoft.com/en-us/library/234b841s(v=vs.110).aspx

-saige-