Question

If not what is the best way to determine if two NameValueCollections objects are equal.

I am using it to determine if two query strings parsed into a namevaluecollection have the same keys and values regardless of order.

Answer 1

Equals does not appear to do what you want. It appears to check reference equality, not that they are equivalent.

The following method should work (using System.Linq), though there’s probably a more efficient way:

public bool CompareNameValueCollections(NameValueCollection nvc1,
                                        NameValueCollection nvc2)
{
    return nvc1.AllKeys.OrderBy(key => key)
                       .SequenceEqual(nvc2.AllKeys.OrderBy(key => key))
        && nvc1.AllKeys.All(key => nvc1[key] == nvc2[key]);
}

Note: If order does matter, the OrderBy statements could be dropped. If there are multiple values per key and you need to check that values are equivalent regardless of order, then the last line could be changed to something like:

        && nvc1.AllKeys
               .All(key => nvc1.GetValues(key)
                               .OrderBy(val => val)
                               .SequenceEqual(nvc2.GetValues(key)
                                                  .OrderBy(val => val)));