Dört İşlem ( Fonksiyon ile )

Public Class Form1

    Dim a, b, sonuc As Integer

    Dim isaret As String

    Function hesap()

        Select Case isaret

            Case "+"

                sonuc = a + b

                MsgBox("Sonuç= " & sonuc)

            Case "-"

                sonuc = a - b

                MsgBox("Sonuç= " & sonuc)

            Case "*"

                sonuc = a * b

                MsgBox("Sonuç= " & sonuc)

            Case "/"

                If b = 0 Then

                    MsgBox("Tanımsız", MsgBoxStyle.Information, "Ercan Akgün")

                Else

                    sonuc = a / b

                    MsgBox("Sonuç= " & sonuc)

                End If

        End Select

        Return sonuc

    End Function

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        a = TextBox1.Text

        b = TextBox2.Text

        Call hesap()

    End Sub

    Private Sub RadioButton1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton1.CheckedChanged

        isaret = "+"

    End Sub

    Private Sub RadioButton2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton2.CheckedChanged

        isaret = "-"

    End Sub

    Private Sub RadioButton3_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton3.CheckedChanged

        isaret = "*"

    End Sub

    Private Sub RadioButton4_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadioButton4.CheckedChanged

        isaret = "/"

    End Sub

End Class