手順 7: 乗算問題と除算問題の追加

このチュートリアルの第 7 部では、乗算問題と除算問題を追加しますが、まず変更方法について考えてみます。 最初の手順は、値を格納することです。

乗算問題と除算問題を追加するには

  1. さらに 4 つの整数変数をフォームに追加します。

    Public Class Form1
    
        ' Create a Random object called randomizer 
        ' to generate random numbers.
        Private randomizer As New Random
    
        ' These integer variables store the numbers 
        ' for the addition problem. 
        Private addend1 As Integer
        Private addend2 As Integer
    
    
        ' These integer variables store the numbers 
        ' for the subtraction problem. 
        Private minuend As Integer
        Private subtrahend As Integer
    
        ' These integer variables store the numbers 
        ' for the multiplication problem. 
        Private multiplicand As Integer
        Private multiplier As Integer
    
        ' These integer variables store the numbers 
        ' for the division problem. 
        Private dividend As Integer
        Private divisor As Integer
    
        ' This integer variable keeps track of the 
        ' remaining time.
        Private timeLeft As Integer
    
    public partial class Form1 : Form
    {
        // Create a Random object called randomizer 
        // to generate random numbers.
        Random randomizer = new Random();
    
        // These integer variables store the numbers 
        // for the addition problem. 
        int addend1;
        int addend2;
    
        // These integer variables store the numbers 
        // for the subtraction problem. 
        int minuend;
        int subtrahend;
    
        // These integer variables store the numbers 
        // for the multiplication problem. 
        int multiplicand;
        int multiplier;
    
        // These integer variables store the numbers 
        // for the division problem. 
        int dividend;
        int divisor;
    
        // This integer variable keeps track of the 
        // remaining time.
        int timeLeft;
    
  2. 以前に実行したように、StartTheQuiz() メソッドを変更して、乗算問題と除算問題に乱数を入力するようにします。

    ''' <summary>
    ''' Start the quiz by filling in all of the problem 
    ''' values and starting the timer. 
    ''' </summary>
    ''' <remarks></remarks>
    Public Sub StartTheQuiz()
    
        ' Fill in the addition problem.
        ' Generate two random numbers to add.
        ' Store the values in the variables 'addend1' and 'addend2'.
        addend1 = randomizer.Next(51)
        addend2 = randomizer.Next(51)
    
        ' Convert the two randomly generated numbers
        ' into strings so that they can be displayed
        ' in the label controls.
        plusLeftLabel.Text = addend1.ToString()
        plusRightLabel.Text = addend2.ToString()
    
        ' 'sum' is the name of the NumericUpDown control.
        ' This step makes sure its value is zero before
        ' adding any values to it.
        sum.Value = 0
    
        ' Fill in the subtraction problem.
        minuend = randomizer.Next(1, 101)
        subtrahend = randomizer.Next(1, minuend)
        minusLeftLabel.Text = minuend.ToString()
        minusRightLabel.Text = subtrahend.ToString()
        difference.Value = 0
    
        ' Fill in the multiplication problem.
        multiplicand = randomizer.Next(2, 11)
        multiplier = randomizer.Next(2, 11)
        timesLeftLabel.Text = multiplicand.ToString()
        timesRightLabel.Text = multiplier.ToString()
        product.Value = 0
    
        ' Fill in the division problem.
        divisor = randomizer.Next(2, 11)
        Dim temporaryQuotient As Integer = randomizer.Next(2, 11)
        dividend = divisor * temporaryQuotient
        dividedLeftLabel.Text = dividend.ToString()
        dividedRightLabel.Text = divisor.ToString()
        quotient.Value = 0
    
        ' Start the timer.
        timeLeft = 30
        timeLabel.Text = "30 seconds"
        Timer1.Start()
    
    End Sub
    
    /// <summary>
    /// Start the quiz by filling in all of the problem 
    /// values and starting the timer. 
    /// </summary>
    public void StartTheQuiz()
    {
        // Fill in the addition problem.
        // Generate two random numbers to add.
        // Store the values in the variables 'addend1' and 'addend2'.
        addend1 = randomizer.Next(51);
        addend2 = randomizer.Next(51);
    
        // Convert the two randomly generated numbers
        // into strings so that they can be displayed
        // in the label controls.
        plusLeftLabel.Text = addend1.ToString();
        plusRightLabel.Text = addend2.ToString();
    
        // 'sum' is the name of the NumericUpDown control.
        // This step makes sure its value is zero before
        // adding any values to it.
        sum.Value = 0;
    
        // Fill in the subtraction problem.
        minuend = randomizer.Next(1, 101);
        subtrahend = randomizer.Next(1, minuend);
        minusLeftLabel.Text = minuend.ToString();
        minusRightLabel.Text = subtrahend.ToString();
        difference.Value = 0;
    
        // Fill in the multiplication problem.
        multiplicand = randomizer.Next(2, 11);
        multiplier = randomizer.Next(2, 11);
        timesLeftLabel.Text = multiplicand.ToString();
        timesRightLabel.Text = multiplier.ToString();
        product.Value = 0;
    
        // Fill in the division problem.
        divisor = randomizer.Next(2, 11);
        int temporaryQuotient = randomizer.Next(2, 11);
        dividend = divisor * temporaryQuotient;
        dividedLeftLabel.Text = dividend.ToString();
        dividedRightLabel.Text = divisor.ToString();
        quotient.Value = 0;
    
        // Start the timer.
        timeLeft = 30;
        timeLabel.Text = "30 seconds"; 
        timer1.Start();
    }
    
  3. 乗算問題と除算問題についても確認するように CheckTheAnswer() メソッドを変更します。

    ''' <summary>
    ''' Check the answers to see if the user got everything right.
    ''' </summary>
    ''' <returns>True if the answer's correct, false otherwise.</returns>
    ''' <remarks></remarks>
    Public Function CheckTheAnswer() As Boolean
    
        If addend1 + addend2 = sum.Value AndAlso 
           minuend - subtrahend = difference.Value AndAlso 
           multiplicand * multiplier = product.Value AndAlso 
           dividend / divisor = quotient.Value Then
    
            Return True
        Else
            Return False
        End If
    
    End Function
    
    /// <summary>
    /// Check the answers to see if the user got everything right.
    /// </summary>
    /// <returns>True if the answer's correct, false otherwise.</returns>
    private bool CheckTheAnswer()
    {
        if ((addend1 + addend2 == sum.Value)
            && (minuend - subtrahend == difference.Value)
            && (multiplicand * multiplier == product.Value)
            && (dividend / divisor == quotient.Value))
            return true;
        else
            return false;
    }
    

    乗算記号 (×) と除算記号 (÷) はキーボードから簡単に入力できないため、Visual C# および Visual Basic では、乗算にはアスタリスク (*)、除算にはスラッシュ記号 (/) を使用します。

  4. タイマーの Tick イベント ハンドラーの最後の部分を、残り時間がなくなったら正しい解答を表示するように変更します。

    Else
        ' If the user ran out of time, stop the timer, show
        ' a MessageBox, and fill in the answers.
        Timer1.Stop()
        timeLabel.Text = "Time's up!"
        MessageBox.Show("You didn't finish in time.", "Sorry!")
        sum.Value = addend1 + addend2
        difference.Value = minuend - subtrahend
        product.Value = multiplicand * multiplier
        quotient.Value = dividend / divisor
        startButton.Enabled = True
    End If
    
    else
    {
        // If the user ran out of time, stop the timer, show 
        // a MessageBox, and fill in the answers.
        timer1.Stop();
        timeLabel.Text = "Time's up!";
        MessageBox.Show("You didn't finish in time.", "Sorry");
        sum.Value = addend1 + addend2;
        difference.Value = minuend - subtrahend;
        product.Value = multiplicand * multiplier;
        quotient.Value = dividend / divisor;
        startButton.Enabled = true;
    }
    
  5. プログラムを保存し、実行します。

    次の図に示すように、クイズの受け手はクイズを完了するためには 4 つの問題に答える必要があります。

    4 つの問題がある計算クイズ
    4 つの問題がある計算クイズ

続行または確認するには