public void String_Concatenate_List_WithSeparator()
        {
            var stringCollection = new System.Collections.Generic.List <string> {
                "23", "45"
            };

            Assert.AreEqual("23,45", stringCollection.Concatenate(","));
        }
        public void String_Concatenate_List()
        {
            var stringCollection = new System.Collections.Generic.List <string> {
                "23", "45"
            };

            Assert.AreEqual("2345", stringCollection.Concatenate());
        }