c# LINQ getting a string that contains all elements in a list
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I'm having trouble coming up with a LINQ to do the following... suppose I have a list of strings below:

    List<string> strings = new List<string>();
    strings.add("one");
    strings.add("two");
    strings.add("three");

I want to be able to get a string that looks like the following:

    string correctString = "onetwothree";

but return null when selecting any other string, e.g.

    string wrongString1 = "onethree"; // returns null
    string wrongString2 = "one"; // returns null
    string wrongString3 = "onetwo"; // returns null
    string wrongString4 = "five"; // returns null

I'm thinking LINQ is the best way to go about it, but unfortunately not having much luck with the select and many statements...

Any suggestions?

Thanks.
