public void Test_Soundex2()
        {
            const string name1 = "Hilbert";
            const string name2 = "Heilbronn";

            var soundex1 = TextConversion.ToSoundex(name1);
            var soundex2 = TextConversion.ToSoundex(name2);

            Assert.AreEqual(soundex1, soundex2);
        }
        public void Test_Soundex1()
        {
            const string name1 = "Euler";
            const string name2 = "Gauss";

            var soundex1 = TextConversion.ToSoundex(name1);
            var soundex2 = TextConversion.ToSoundex(name2);

            Assert.AreEqual("E460", soundex1);
            Assert.AreEqual("G200", soundex2);
        }