Option Strict On
Option Explicit On
Public Class frmMain
    'Variables global to the form
    Dim randNum1, randNum2 As Single

    'When the form loads...
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Acts like it is clicking the generate new range button
        btnNewRange.PerformClick()
    End Sub

    'When the new range button is clicked...
    Private Sub btnNewRange_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNewRange.Click
        'Generates new range and then displays the question in the question label
        randNum1 = Rnd()
        randNum2 = randNum1 + Rnd()

        lblQuestion.Text = "Please enter a number between " & CStr(randNum1) & " and " & CStr(randNum2)
    End Sub

    'When the submit button is clicked...
    Private Sub btnSubmit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
        Dim answer As Double
        'First checks if the answer in the text box is a number
        If IsNumeric(txtAnswer.Text) Then
            answer = CDbl(txtAnswer.Text)
            'Then it checks if the answer is in the correct range, then displays appropriate message
            If answer > randNum1 And answer < randNum2 Then
                MessageBox.Show("You are correct!", "You are correct!")
            Else
                MessageBox.Show("You are incorrect...", "You are incorrect...")
            End If
        Else
            MessageBox.Show("Please Enter a Valid Number", "Please Enter a Valid Number")
        End If
    End Sub
End Class