Question

I have a question for how to compare two strings.

here is the code.

        string stringA = "This is a test item";
        string stringB = "item test a is This";

Obviously, stringB contains every words from stringA, but in a different order.

My desired result should be TRUE.

My question is, what should I do? I have tried to use the .Contains() method, but the result is FALSE.

Thanks everyone.

UPDATES

Thanks everyone for the kindly replies.

Here is my clarification

I am actually building a database search function by using LINQ and EF.

Assume that, an item has its name as “This is a test item”.

If user input “test a is this”, I would like the function smart enough to catch the item mentioned above.

Any suggestion?

ANOTHER UPDATE

Thanks again for all your help.

I do like Peter Ritchie’s, codesparkle’s, Dave’s and EdFred’s suggestion.

Answer 1

Building on Peter Richie’s excellent suggestion, using Array.Sort() instead of List<T>.Sort(), without the duplication but packed into a neat extension method:

public static bool ContainsSameWordsAs(this string first, string second)
{
    return first.GetSortedWords().SequenceEqual(second.GetSortedWords());
    // if upper and lower case words should be seen as identical, use:
    // StringComparer.OrdinalIgnoreCase as a second argument to SequenceEqual
}

private static IEnumerable<string> GetSortedWords(this string source)
{
    var result = source.Split().ToArray();
    Array.Sort(result);
    return result;
}

Usage

string stringA = "This is a test item";
string stringB = "item test a is This";
string stringC = "Not the Same is This";
bool result = stringA.ContainsSameWordsAs(stringB);    // true
bool different = stringA.ContainsSameWordsAs(stringC); // false

---

Edit: It’s hard to understand why you accepted an answer that does not comply with the requirements stated in your question. If you really want the strings "This is a test item" and "test a is this" to match, you’d need to use something a bit more involved, such as:

public static bool ContainsSameWordsAs(this string first, string second)
{
    var ignoreCase = StringComparer.OrdinalIgnoreCase;
    return first.Split().Any(word => second.Split().Contains(word, ignoreCase));
}

You may want to come up with a better algorithm though, as this one is extremely loose — two identical words will be enough to count as a match. But this one will match your requirements as stated in the question.