C#
Running the quiz
Learn to ask questions in turn with the Run method.
Playing the quiz
In this lesson we add a Run method to the Quiz class. This method takes a string[] of answers, iterates each question, compares the answer and prints correct/wrong.
The loop for (int i = 0; i < questions.Count; i++) walks each question. questions[i].Text gives the question text, questions[i].Answer the expected answer. The comparison answers[i] == questions[i].Answer checks the answer. If correct, print "Correct"; otherwise print "Wrong".
Array parameter
The Run method takes a string[] parameter; this array holds one answer per question. Call: quiz.Run(new[] { "Ankara" }).
new[] { ... } creates a new array. The array length must match the question count; otherwise answers[i] may fail. In this lesson the answers are sent from code; in a real app you could read them with Console.ReadLine().
Exercise Play the quiz
Add a public void Run(string[] answers) method to Quiz. In its body use a for loop to walk the questions; print questions[i].Text, then if answers[i] == questions[i].Answer print "Correct", otherwise "Wrong". In Main, add one question and call quiz.Run(new[] { "Ankara" }).
Show example solution
Add `public void Run(string[] answers) { for (int i = 0; i < questions.Count; i++) { Console.WriteLine(questions[i].Text); if (answers[i] == questions[i].Answer) { Console.WriteLine("Correct"); } else { Console.WriteLine("Wrong"); } } }` to Quiz. In Main write `var quiz = new Quiz(); quiz.AddQuestion(new Question { Text = "Capital?", Answer = "Ankara" }); quiz.Run(new[] { "Ankara" });`.
Example solution:
using System;
using System.Collections.Generic;
class Question
{
public string Text;
public string Answer;
}
class Quiz
{
private List<Question> questions = new List<Question>();
public void AddQuestion(Question q)
{
questions.Add(q);
}
public int Count()
{
return questions.Count;
}
public void Run(string[] answers)
{
for (int i = 0; i < questions.Count; i++)
{
Console.WriteLine(questions[i].Text);
if (answers[i] == questions[i].Answer)
{
Console.WriteLine("Correct");
}
else
{
Console.WriteLine("Wrong");
}
}
}
}
class Program
{
static void Main()
{
var quiz = new Quiz();
quiz.AddQuestion(new Question { Text = "Capital?", Answer = "Ankara" });
quiz.Run(new[] { "Ankara" });
}
}
Test yourself
-
Match: Run method parts
- for
- question loop
- answers[i]
- student answer
- questions[i]
- question record
- ==
- comparison
-
What should the Run method do?
- Show only the first question.
- Print nothing.
- Shuffle the questions.
- Iterate the questions, compare answers and print correct/wrong.
Show answer
Iterate the questions, compare answers and print correct/wrong. — Correct. Run walks all questions and compares answers.
-
Fill in the blank: for loop
for (____; i < questions.Count; i++)
Show answer
for (int i = 0; i < questions.Count; i++)
Next lesson: Score calculation
