Add project files.

LearningChineseSimplified/ExtensionMethods/StringExtensions.cs

@@ -0,0 +1,15 @@
+namespace LearningChineseSimplified.ExtensionMethods
+{
+    public static class StringExtensions
+    {
+        public static string ToTitleCase(this string input)
+        {
+            char firstLetter = input[0];
+            firstLetter = char.ToUpper(firstLetter);
+
+            string restOfString = input.Substring(1, input.Length - 1);
+
+            return firstLetter + restOfString;
+        }
+    }
+}