Imports System.DirectoryServices
Imports System.Security.Cryptography.X509Certificates

Public Class Form1
    Dim a As Double
    Dim b As Double
    Dim result As Double
    Dim memory As Double = 0
    Private Sub Label2_Click(sender As Object, e As EventArgs) Handles Label2.Click

    End Sub

    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
        TextBox1.Text = TextBox1.Text.Remove(TextBox1.Text.Length - 1)
    End Sub

    Private Sub Button5_Click(sender As Object, e As EventArgs) Handles num1.Click
        TextBox1.Text = TextBox1.Text + "1"
    End Sub

    Private Sub Button6_Click(sender As Object, e As EventArgs) Handles num2.Click
        TextBox1.Text = TextBox1.Text + "2"
    End Sub

    Private Sub Button7_Click(sender As Object, e As EventArgs) Handles num3.Click
        TextBox1.Text = TextBox1.Text + "3"
    End Sub

    Private Sub Button9_Click(sender As Object, e As EventArgs) Handles num4.Click
        TextBox1.Text = TextBox1.Text + "4"
    End Sub

    Private Sub Button10_Click(sender As Object, e As EventArgs) Handles num5.Click
        TextBox1.Text = TextBox1.Text + "5"
    End Sub

    Private Sub Button11_Click(sender As Object, e As EventArgs) Handles num6.Click
        TextBox1.Text = TextBox1.Text + "6"
    End Sub

    Private Sub Button17_Click(sender As Object, e As EventArgs) Handles num7.Click
        TextBox1.Text = TextBox1.Text + "7"
    End Sub

    Private Sub Button18_Click(sender As Object, e As EventArgs) Handles num8.Click
        TextBox1.Text = TextBox1.Text + "8"
    End Sub

    Private Sub Button19_Click(sender As Object, e As EventArgs) Handles num9.Click
        TextBox1.Text = TextBox1.Text + "9"
    End Sub

    Private Sub Button14_Click(sender As Object, e As EventArgs) Handles num0.Click
        TextBox1.Text = TextBox1.Text + "0"
    End Sub

    Private Sub Button8_Click(sender As Object, e As EventArgs) Handles Delenie.Click
        TextBox1.Text = TextBox1.Text + "/"
    End Sub

    Private Sub Button12_Click(sender As Object, e As EventArgs) Handles Multiply.Click
        TextBox1.Text = TextBox1.Text + "*"
    End Sub

    Private Sub Button20_Click(sender As Object, e As EventArgs) Handles Minus.Click
        TextBox1.Text = TextBox1.Text + "-"
    End Sub

    Private Sub Button16_Click(sender As Object, e As EventArgs) Handles Plus.Click
        TextBox1.Text = TextBox1.Text + "+"
    End Sub

    Private Sub Button24_Click(sender As Object, e As EventArgs) Handles Ravno.Click
        Dim text As String = TextBox1.Text
        If text.Contains("+") Then
            Dim parts() As String = text.Split("+")
            TextBox2.Text = (Val(parts(0))) + Val(parts(1)).ToString()
        ElseIf text.Contains("-") Then
            Dim parts() As String = text.Split("-")
            TextBox2.Text = (Val(parts(0))) - Val(parts(1)).ToString()
        ElseIf text.Contains("/") Then
            Dim parts() As String = text.Split("/")
            If Val(parts(1)) <> 0 Then
                TextBox2.Text = (Val(parts(0))) / Val(parts(1)).ToString()
            Else
                TextBox2.Text = "Делить на ноль нельзя!"
            End If
        ElseIf text.Contains("*") Then
            Dim parts() As String = text.Split("*")
            TextBox2.Text = (Val(parts(0))) * Val(parts(1)).ToString()
        End If
    End Sub

    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        TextBox1.Clear()
        TextBox2.Clear()
    End Sub

    Private Sub Button15_Click(sender As Object, e As EventArgs) Handles Button15.Click
        If TextBox1.Text <> "" Then
            Dim number As Integer = CInt(TextBox1.Text)
            Dim remainder As Integer = number Mod 2
            TextBox2.Text = remainder.ToString()
        End If
    End Sub

    Private Sub Button13_Click(sender As Object, e As EventArgs) Handles Button13.Click
        Dim s As String = TextBox1.Text
        If s = "" Or s = "-" Then
            TextBox1.Text = "-"
        ElseIf s.StartsWith("-") Then
            TextBox1.Text = s.Substring(1)
        Else
            TextBox1.Text = "-" & s
        End If
    End Sub

    Private Sub Button21_Click(sender As Object, e As EventArgs) Handles Button21.Click
        If memory <> 0 Then
            TextBox1.Text = memory.ToString()
        Else
            TextBox1.Text = ("Память пуста!")
        End If
    End Sub

    Private Sub Button22_Click(sender As Object, e As EventArgs) Handles Button22.Click
        Try
            Dim value As Double
            If TextBox2.Text <> "" AndAlso TextBox2.Text <> "0" Then
                value = Val(TextBox2.Text)
            Else
                TextBox1.Text = ("Нет значения для добавления в память")
                Return
            End If
            memory += value
        Catch ex As Exception
            MessageBox.Show("Ошибка")
        End Try
    End Sub

    Private Sub Button23_Click(sender As Object, e As EventArgs) Handles Button23.Click
        If memory <> 0 Then
            TextBox1.Text = ("Память очищена")
            memory = 0
        Else
            TextBox1.Text = ("Память уже пуста!")
        End If
    End Sub
End Class