Finished Defining a Delegate

gradebook/test/GradeBook.Tests/TypeTests.cs

@@ -4,8 +4,26 @@ using Xunit;
 namespace GradeBook.Tests
 {
     using GradeBook;
+ 
+    public delegate string WriteLogDelegate(string logMessage);
+
     public class TypeTests
     {
+        [Fact]
+        public void WriteLogDelegateCanPointToMethod()
+        {
+            string msg = "test";
+
+            WriteLogDelegate log = new WriteLogDelegate(ReturnMessage); // Instantiate a delegate
+            var result = log(msg); // Invoking a delegate
+            Assert.Equal(result, msg);
+        }
+
+        string ReturnMessage(string message)
+        {
+            return message;
+        }
+
         [Fact]
         public void ValueTypesAlsoPassByValue()
         {