Démarche à suive pour créer une application de calculatrice simple en utilisant les contrôles de bouton et de zone de texte en Visual Basic DotNet:
Conception (design) :
Public Class frmCalculatrice_02
Dim begin As Boolean = True
Dim firstNumber As Decimal
Dim secondNumber As Decimal
Dim result As Decimal
Dim operation As String
Private Sub Button_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnDecimal.Click, btn0.Click, btn1.Click, btn2.Click, btn3.Click, btn4.Click, btn5.Click, btn6.Click, btn7.Click, btn8.Click, btn9.Click
Dim button As Button = CType(sender, Button)
If begin Then txtResult.Clear()
If txtResult.Text = "," Or txtResult.Text = "0," Then txtResult.Text = "0,"
If button.Text = "," And txtResult.Text.Contains(",") Then
txtResult.Text = txtResult.Text
Else
txtResult.Text = txtResult.Text & button.Text
End If
begin = False
End Sub
Private Sub Operation_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnAdd.Click, btnSubtract.Click, btnMultiply.Click, btnDivide.Click
Dim button As Button = CType(sender, Button)
firstNumber = Convert.ToDecimal(txtResult.Text)
operation = button.Text
begin = True
End Sub
Private Sub btnEqual_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnEqual.Click
secondNumber = Convert.ToDecimal(txtResult.Text)
Select Case operation
Case "+"
result = firstNumber + secondNumber
Case "-"
result = firstNumber - secondNumber
Case "*"
result = firstNumber * secondNumber
Case "/"
If secondNumber <> 0 Then
result = firstNumber / secondNumber
Else
MessageBox.Show("Division par zéro interdite", "Erreur", MessageBoxButtons.OK, MessageBoxIcon.Error)
Exit Sub
End If
End Select
begin = True
txtResult.Text = result.ToString()
End Sub
Private Sub ButtonClear_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnC.Click
txtResult.Text = "0,"
firstNumber = 0
secondNumber = 0
result = 0
operation = String.Empty
End Sub
Private Sub btnOFF_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOFF.Click
btnON.Visible = True
pnlCalc.Visible = False
End Sub
Private Sub btnON_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnON.Click
pnlCalc.Visible = True
btnON.Visible = False
End Sub
Private Sub frmCalculatrice_01_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
pnlCalc.Controls.Remove(btnON)
End Sub
End Class Notez que ce code est juste un exemple et qu’il peut être amélioré pour prendre en compte des erreurs de l’utilisateur et d’autres fonctionnalités avancées.