private static void exampleDelegate()
{
Console.WriteLine("Starting Delegate example");
GradeBook book = new GradeBook();
book.AddGrade(92);
book.AddGrade(34);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
//using delegate - this will later be triggered any time the name changes later.
// book.NameChanged = new NameChangedDelegate(OnNameChanged);
//alternate method : multi cast delegate
//multiple subscribers to execute when the event occurs
book.NameChanged += OnNameChanged;
book.NameChanged += OnNameChanged2;
//can unsubscribe from this event
// book.NameChanged -= OnNameChanged2;
book.Name = "changed name";
WriteNames(book.Name);
Console.WriteLine("Avg:" + stats.AverageGrade);
Console.WriteLine("Lowest" + stats.LowestGrade);
Console.WriteLine("Highest" + stats.HighestGrade);
}
static void Main(string[] args)
{
Arrays();
//Immutable();
GradeBook book = new GradeBook("Scott's book");
book.AddGrade(91f);
book.AddGrade(89.1f);
book.AddGrade(75f);
GradeStatistics stats = book.ComputeStatistics();
book.NameChanged = new NamedChangedDelegate(OnNameChanged);
book.NameChanged += OnNameChanged;
book.NameChanged += OnNameChanged2;
book.Name = "Allen's book";
WriteNames(book.Name);
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.LowestGrade);
Console.WriteLine(stats.HighestGrade);
Console.ReadLine();
}
public void LetterGradeTest()
{
var gradeBook1 = new GradeBook();
gradeBook1.AddGrade(90);
gradeBook1.AddGrade(100);
var stats1 = gradeBook1.ComputeStatistics();
Assert.AreEqual("A", stats1.LetterGrade);
var gradeBook2 = new GradeBook();
gradeBook2.AddGrade(80);
gradeBook2.AddGrade(87);
var stats2 = gradeBook2.ComputeStatistics();
Assert.AreEqual("B", stats2.LetterGrade);
var gradeBook3 = new GradeBook();
gradeBook3.AddGrade(77);
gradeBook3.AddGrade(79);
var stats3 = gradeBook3.ComputeStatistics();
Assert.AreEqual("C", stats3.LetterGrade);
var gradeBook4 = new GradeBook();
gradeBook4.AddGrade(67);
gradeBook4.AddGrade(61);
var stats4 = gradeBook4.ComputeStatistics();
Assert.AreEqual("D", stats4.LetterGrade);
var gradeBook5 = new GradeBook();
gradeBook5.AddGrade(58);
gradeBook5.AddGrade(12);
var stats5 = gradeBook5.ComputeStatistics();
Assert.AreEqual("F", stats5.LetterGrade);
}
public void ComputesLetterGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(88);
GradeStatistics result = book.ComputeStatistics();
Assert.AreEqual("B", result.LetterGrade);
}
private static void WriteResults(GradeBook book)
{
GradeStatistics stats = book.ComputeStatistics();
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", stats.HighestGrade);
WriteResult("Lowest", stats.LowestGrade);
WriteResult(stats.Description, stats.LetterGrade);
}
public void ComputeLowestGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(90.5f);
book.AddGrade(82);
GradeStatistics result = book.ComputeStatistics();
Assert.AreEqual(82, result.LowestGrade);
}
public void ComputeAverageGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(90.5f);
book.AddGrade(82);
GradeStatistics result = book.ComputeStatistics();
Assert.AreEqual(86.25, result.AverageGrade);
}
public void LowestGradeTest()
{
var gradeBook = new GradeBook();
gradeBook.AddGrade(90);
gradeBook.AddGrade(10);
var stats = gradeBook.ComputeStatistics();
Assert.AreEqual(10, stats.LowestGrade);
}
public void ComputesLowestGrade()
{
Grades.GradeBook book = new Grades.GradeBook();
book.AddGrade(10);
book.AddGrade(90);
Grades.GradeStatistics result = book.ComputeStatistics();
Assert.Equal(10, result.LowestGrade);
}
public void ComputesHighestGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(10);
book.AddGrade(90);
GradeStatistics result = book.ComputeStatistics();
Assert.AreEqual(90, result.HighestGrade);
}
public void AverageGradeTest()
{
var gradeBook = new GradeBook();
gradeBook.AddGrade(90);
gradeBook.AddGrade(10);
gradeBook.AddGrade(0);
var stats = gradeBook.ComputeStatistics();
Assert.AreEqual(33.33f, stats.Average, 0.01);
}
public void ComputesAverageGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics result = book.ComputeStatistics();
Assert.AreEqual(85.16, result.AverageGrade, 0.01);
}
public void ComputesAverageGrade()
{
Grades.GradeBook book = new Grades.GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
Grades.GradeStatistics result = book.ComputeStatistics();
Assert.Equal(85.17, result.AverageGrade, 2);
}
private static void WriteResults(GradeBook book)
{
//Instantiate the GradeStatistics
GradeStatistics stats = book.ComputeStatistics();
WriteResults("Average", stats.AverageGrade);
WriteResults("Highest", stats.HighestGrade);
WriteResults("Lowest", stats.LowestGrade);
WriteResults(stats.Description, stats.LetterGrade);
}
public void CalculatesHighestGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(90f);
book.AddGrade(50f);
GradeStatistics stats = book.ComputeStatistics();
Assert.AreEqual(90f, stats.HighestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
public void AverageGradeTest()
{
GradeBook book = new GradeBook();
book.AddGrade(90f);
book.AddGrade(50f);
GradeStatistics stats = book.ComputeStatistics();
Assert.AreEqual(70, stats.AverageGrade);
}
public void LowestGradeTest()
{
GradeBook book = new GradeBook();
book.AddGrade(90);
book.AddGrade(50);
GradeStatistics stats = book.ComputeStatistics();
Assert.AreEqual(50, stats.LowestGrade);
}
static void WriteResults(GradeBook book)
{
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("___________________________________________");
Console.WriteLine($"Welcome to: {book.Name}");
Console.WriteLine("___________________________________________");
Console.WriteLine($"Class Average: {stats.AverageGrade}");
Console.WriteLine($"Class Highest: {stats.HighestGrade}");
Console.WriteLine($"Class Lowest: {stats.LowestGrade}");
}
private static void WriteResults(GradeBook book)
{
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(book.Name);
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", stats.HighestGrade);
WriteResult("Lowest", stats.LowestGrade);
WriteResult("Grade", stats.LetterGrade);
WriteResult("Description", stats.Description);
}
private static void WriteResults(GradeBook book)
{
SaveGrades(book);
GradeSatistics stats = book.ComputeStatistics();
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", stats.HighestGrade);
WriteResult("Lowest", stats.LowestGrade);
WriteResult(stats.Description, stats.LetterGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args) // What is this?
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f); // f indifcates it's a float. Otherwise it gives error 'cannot convert from double to float'.
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook("Borys's Book");
try
{
using (FileStream stream = File.Open("grade.txt", FileMode.Open))
using (StreamReader reader = new StreamReader(stream))
{
string line = reader.ReadLine();
while (line != null)
{
float grade = float.Parse(line);
book.AddGrade(grade);
line = reader.ReadLine();
}
}
}
catch (FileNotFoundException ex)
{
Console.WriteLine("Could not locate the file grades.txt");
return;
}
catch (UnauthorizedAccessException ex)
{
Console.WriteLine("No access");
return;
}
book.WriteGrades(Console.Out);
// dajcie zapętlenie do poprawnego wpisania nazwy dziennika. String.IsNullOrEmpty
try
{
Console.WriteLine("Please enter a name for the book");
book.Name = Console.ReadLine();
}
catch (ArgumentException ex)
{
Console.WriteLine("Invalid Name");
}
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
Console.WriteLine("{0} - {1}", stats.LetterGrade, stats.Description);
Console.ReadLine();
}
static void Main(string[] args)
{
GradeBook book = new GradeBook("Delan's Book");
book.AddGrade(91);
book.AddGrade(89.1f);
book.AddGrade(90f);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("Average: " + stats.AverageGrade);
Console.WriteLine("Highest: " + stats.HighestGrade);
Console.WriteLine("Lowest: " + stats.LowestGrade);
Console.WriteLine("{0}, {1}", stats.LetterGrade, stats.Description);
}
public void CalculateHighestGrade()
{
GradeBook book = new GradeBook();
book.AddGrade(89);
book.AddGrade(70);
book.AddGrade(42);
GradeStatistics stats = book.ComputeStatistics();
float highestGrade = stats.HighestGrade;
Assert.AreEqual(highestGrade, 89f);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook(); /* the first 'GradeBook' implies class type GradeBook, this object is now garbage because of the new book object below */
book.AddGrade(91f);
book.AddGrade(89.5f); /* the 'f' tells the compiler 89.5 is a float otherwise you get an error since it assumes its a double */
book.AddGrade(75f);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.LowestGrade);
Console.WriteLine(stats.HighestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(85);
book.AddGrade(89.5f);
GradeStatistics stats = book.ComputeStatistics();
GradeBook book2 = book;
book2.AddGrade(75);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook(); //Instanciación
book.AddGrade(91);
book.AddGrade(88.5);
book.AddGrade(87.5);
GradeStaistics stats = book.ComputeStatistics();
System.Console.WriteLine("Average: " + stats.AverageGrade);
System.Console.WriteLine("Max: " + stats.HighestGrade);
System.Console.WriteLine("Min: " + stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", (int)stats.HighestGrade);
WriteResult("Lowest", stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f); // Forces this number to be a float since it would normally be a double
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(81.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("The highest grade is " + stats.HighestGrade);
Console.WriteLine("The average grade is " + stats.AverageGrade);
Console.WriteLine("The lowest grade is " + stats.LowestGrade);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello! this is the real life?");
GradeBook book = new GradeBook(); //invoke the constructor to make a new Gradebook object
book.AddGrade(91);
book.AddGrade(89.5f); // apply an 'f' to show that it's a floating point number
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(90.5);
book.AddGrade(85.5);
book.AddGrade(75.5);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("List of Grades in the Grade Book");
book.DisplayGradeBook();
Console.WriteLine("Average Grade " + stats.AverageGrade);
Console.WriteLine("Highest Grade " + stats.HighestGrade);
Console.WriteLine("Lowest Grade " + stats.LowestGrade);
}
static void Main(string[] args)
{
var book = new GradeBook();
book.AddGrade(91f);
book.AddGrade(89.5f);
book.AddGrade(75f);
var gradeStats = book.ComputeStatistics();
Console.WriteLine($"The highest grade in the book is {gradeStats.HighestGrade}");
Console.WriteLine($"The lowest grade in the book is {gradeStats.LowestGrade}");
Console.WriteLine($"All grades averaged {gradeStats.AverageGrade}");
}
static void Main(string[] args)
{
GradeBook book = new GradeBook("Delan's Book");
book.AddGrade(91);
book.AddGrade(89.1f);
book.AddGrade(90f);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("Average: " + stats.AverageGrade);
Console.WriteLine("Highest: " + stats.HighestGrade);
Console.WriteLine("Lowest: " + stats.LowestGrade);
Console.WriteLine("{0}, {1}", stats.LetterGrade, stats.Description);
}
private static void GenerateResults(GradeBook book)
{
Statistics stats = book.ComputeStatistics();
if (stats.GetActiveStats() == true)
{
writeResult("Highest Grade", stats.GetHighestGrade());
writeResult("Lowest Grade", stats.GetLowestGrade());
writeResult("Average Grade", stats.GetAverGrade());
writeResult(stats.Description, stats.LetterGrade);
}
else
{
Console.WriteLine("There are no grades to compute!");
}
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello World!");
var book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(49.2f);
var stats = book.ComputeStatistics();
Console.WriteLine($"min = {stats.lowest}, max = {stats.highest}, avg = {stats.average}");
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(76);
book.AddGrade(12);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine($"Max grade is {stats.maxGrade}\n");
Console.WriteLine($"Min grade is {stats.minGrade}\n");
Console.WriteLine($"Average grade is {stats.avgGrade}\n");
}
private static void ClassesAndTypes()
{
GradeBook book = new GradeBook();
//or default value GradeBook book = new GradeBook(string name ="Default Book");
book.AddGrade(92);
book.AddGrade(34);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
WriteNames(book.Name);
Console.WriteLine("Avg:" + stats.AverageGrade);
Console.WriteLine("Lowest" + stats.LowestGrade);
Console.WriteLine("Highest" + stats.HighestGrade);
}
static void Main(string[] args)
{
var book = new GradeBook();
book.AddGrade(91);
book.AddGrade(81.5f);
book.AddGrade(77);
book.NameChange = new NameChangedDelegate(OnNameChanged);
book.Name = "Laney ";
Console.WriteLine(book.Name);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine($"Average : {stats.AvarageGrade}" +
$" \r\nHighst : {stats.HighstGrade}" +
$"\r\nLowst: {stats.LowesGrade}");
}
static void Main(string[] args)
{
SpeechSynthesizer speaker = new SpeechSynthesizer();
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(80.5f);
book.AddGrade(60);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine($"Highest grade = {stats.HighestGrade}");
Console.WriteLine($"Lowest grade = {stats.LowestGrade}");
Console.WriteLine($"Average grade = {stats.AverageGrade}");
}
static void Main(string[] args)
{
GradeBook book = new GradeBook("Scott's Book");
try
{
using (FileStream stream = File.Open("grades.txt", FileMode.Open))
using (StreamReader reader = new StreamReader(stream))
{
string line = reader.ReadLine();
while (line != null)
{
float grade = float.Parse(line);
book.AddGrade(grade);
line = reader.ReadLine();
}
}
}
catch (FileNotFoundException ex)
{
Console.WriteLine("Could not locate the file grades.txt");
return;
}
catch (UnauthorizedAccessException ex)
{
Console.WriteLine("No access");
return;
}
book.WriteGrades(Console.Out);
try
{
//Console.WriteLine("Please enter a name for the book");
//book.Name = Console.ReadLine();
}
catch (ArgumentException)
{
Console.WriteLine("Invalid name");
}
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.LowestGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine("{0} {1}", stats.LetterGrade, stats.Description);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello! this is the real life?");
GradeBook book = new GradeBook(); //invoke the constructor to make a new Gradebook object
book.AddGrade(91);
book.AddGrade(89.5f); // apply an 'f' to show that it's a floating point number
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello! I'm going to speak your grades.");
GradeBook book = new GradeBook(); //constructor, new kw is invoking a new instance of GradeBook
book.AddGrade(91);
book.AddGrade(89.5f); //The f instructs to make this a float.
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.HighestGrade); // SNIPPET - cw (tab tab)
Console.WriteLine(stats.AverageGrade);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello! This is the grade book program");
GradeBook book = new GradeBook();
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AverageGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
var book = new GradeBook();
book.AddGrade(80);
book.AddGrade(79.5f);
book.AddGrade(56);
var stats = book.ComputeStatistics();
Console.WriteLine(book.Name);
WriteResult("Average grade", stats.AverageGrade);
WriteResult("Lowest grade", stats.LowestGrade);
WriteResult("Highest grade", stats.HighestGrade);
WriteResult("Grade", stats.LetterGrade);
Console.ReadLine();
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello!, this is the grade book program");
GradeBook book = new GradeBook();
// book.NameChanged = new NameChangedDelegate(OnNameChanged);
//book.NameChanged = new NameChangedDelegate(OnNameChanged2);
book.NameChanged += new NameChangedDelegate(OnNameChanged);
// book.NameChanged += new NameChangedDelegate(OnNameChanged2);
//book.NameChanged = null;
try
{
Console.WriteLine("Enter a name");
book.Name = Console.ReadLine();
}
catch (ArgumentException ex)
{
Console.WriteLine(ex.Message);
}
//book.Name = "Kumar's Grade Book";
//book.Name = "Kumar' Grade Book";
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
book.WriteGrades(Console.Out);
GradeStatistics stats = book.ComputeStatistics();
////book.LowestGrade();
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest Grade", (int)stats.HighestGrade);
WriteResult("Lowest Grade", stats.LowestGrade);
WriteResult(stats.Description, stats.LetterGrade);
Console.ReadLine();
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.NameChanged += OnNameChanged;
book.Name = "Ranjith Grade book";
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(book.Name);
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", (int)stats.HighestGrade);
WriteResult("Lowest", (int)stats.LowestGrade);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello! This is a Gradebook porgram");
GradeBook book = new GradeBook();
book.AddGrade(43);
book.AddGrade(91.56f);
book.AddGrade(77);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(stats.AvgGrade);
Console.WriteLine(stats.HighestGrade);
Console.WriteLine(stats.LowestGrade);
}
static void Main(string[] args)
{
SpeechSynthesizer synth = new SpeechSynthesizer();
synth.Speak("Hello, World!");
Arrays();
Immutable();
PassByValueAndRef();
GradeBook book = new GradeBook();
book.AddGrade(91f);
book.AddGrade(89.5f);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine("Average grade: {0}", stats.AverageGrade);
Console.WriteLine("Highest grade: {0}", stats.HighestGrade);
Console.WriteLine("Lowest grade: {0}", stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook();
book.NameChanged += new NameChangedDelegate(OnNameChanged);
book.Name = "Randy's Grade Book";
book.Name = "Grade Book";
book.Name = null;
book.AddGrade(91);
book.AddGrade(89.5f);
book.AddGrade(75);
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(book.Name);
WriteResult("Average", stats.AverageGrade);
WriteResult("Highest", (int)stats.HighestGrade);
WriteResult("Lowest", stats.LowestGrade);
}
static void Main(string[] args)
{
GradeBook book = new GradeBook("Éder's book");
book.AddGrade(77);
book.AddGrade(54.25f);
book.AddGrade(41f);
GradeStatistics stats = book.ComputeStatistics();
book.NameChanged += OnNameChanged;
book.NameChanged += OnNameChanged;
book.NameChanged += OnNameChanged2;
book.NameChanged -= OnNameChanged;
book.Name = "Henrique's book";
WriteNames(book.Name);
//Console.WriteLine(stats.AverageGrade);
//Console.WriteLine(stats.LowestGrade);
//Console.WriteLine(stats.HighestGrade);
}