Add anagram in C#

anagram/AnagramTest.cs

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+using NUnit.Framework;
+
+[TestFixture]
+public class AnagramTest
+{
+    [Test]
+    public void NoMatches ()
+    {
+        Anagram detector = new Anagram("diaper");
+        string[] words = new string[] { "hello", "world", "zombies", "pants" };
+        string[] results = new string[0];
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+
+    [Test]
+    public void DetectSimpleAnagram ()
+    {
+        Anagram detector = new Anagram("ant");
+        string[] words = new string[] { "tan", "stand", "at" };
+        string[] results = new string[] { "tan" };
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void DetectMultipleAnagrams ()
+    {
+        Anagram detector = new Anagram("master");
+        string[] words = new string[] { "stream", "pigeon", "maters" };
+        string[] results = new string[] { "maters", "stream" };
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void DoesNotConfuseDifferentDuplicates ()
+    {
+        Anagram detector = new Anagram("galea");
+        string[] words = new string[] { "eagle" };
+        string[] results = new string[0];
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void IdenticalWordIsNotAnagram ()
+    {
+        Anagram detector = new Anagram("corn");
+        string[] words = new string[] { "corn", "dark", "Corn", "rank", "CORN", "cron", "park" };
+        string[] results = new string[] { "cron" };
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void EliminateAnagramsWithSameChecksum ()
+    {
+        Anagram detector = new Anagram("mass");
+        string[] words = new string[] { "last" };
+        string[] results = new string[0];
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void EliminateAnagramSubsets ()
+    {
+        Anagram detector = new Anagram("good");
+        string[] words = new string[] { "dog", "goody" };
+        string[] results = new string[0];
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void DetectAnagrams ()
+    {
+        Anagram detector = new Anagram("allergy");
+        string[] words = new string[] { "gallery", "ballerina", "regally", "clergy", "largely", "leading" };
+        string[] results = new string[] { "gallery", "largely", "regally" };
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+    [Test]
+    public void AnagramsAreCaseInsensitive ()
+    {
+        Anagram detector = new Anagram("Orchestra");
+        string[] words = new string[] { "cashregister", "Carthorse", "radishes" };
+        string[] results = new string[] { "Carthorse" };
+        Assert.AreEqual(results, detector.Match(words));
+    }
+
+}

anagram/Example.cs

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+using System;
+using System.Linq;
+using System.Collections.Generic;
+
+public class Anagram
+{
+    private string baseWord;
+
+    public Anagram (string baseWord)
+    {
+        this.baseWord = baseWord;
+    }
+
+    public string[] Match (string[] potentialMatches)
+    {
+        List<string> matches = new List<string>();
+
+        foreach (string word in potentialMatches)
+        {
+            if (IsWordAnagramOfBaseWord(word))
+            {
+                matches.Add(word);
+            }
+        }
+
+        return matches.OrderBy(word => word).ToArray();
+    }
+
+    private bool IsWordAnagramOfBaseWord (string word)
+    {
+        return (IsNotTheSameWordAsBaseWord(word) && HasSameLettersAsBaseWord(word));
+    }
+
+    private bool IsNotTheSameWordAsBaseWord (string word)
+    {
+        return ! baseWord.Equals(word,StringComparison.OrdinalIgnoreCase);
+    }
+
+    private bool HasSameLettersAsBaseWord (string word)
+    {
+        return SortedCharArrayForString(baseWord).Equals(SortedCharArrayForString(word));
+    }
+
+    private string SortedCharArrayForString (string word)
+    {
+        return String.Concat(word.ToLower().OrderBy(letter => letter));
+    }
+}