public void ReadFile()
        {
            ErrorItem item;

            using (new TestResource("HelloWorld.txt"))
            {
                item = new ErrorItem("HelloWorld.txt", 1);

                Assert.That(item.ReadFile(), Is.Not.Null);
                Assert.That(item.ReadFile(), Is.EqualTo("Hello world!"));
            }

            return;
        }        
 public void ReadFile_Throws_FileNotExistException()
 {
     ErrorItem item = new ErrorItem("C:\\unknown\\unknown.txt", 1);
     item.ReadFile(); // throws exception
 }