Develop program for Book Shop in vb.net GUI Microprojets I scheme

GUI:















CODE:

Public Class Form1
    Dim total As Double
    REM Dim keyascii, vbkeydecpt, vbkeyback As Single
    Dim cost, discount, nobooks As Single



    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        cbobooktype.Items.Add("Mathematics")
        cbobooktype.Items.Add("Accounting")
        cbobooktype.Items.Add("Economics")
        cbobooktype.Items.Add("English")
        cbobooktype.Items.Add("Marketing")
        cbobuyer.Items.Add("Student")
        cbobuyer.Items.Add("Teacher")
        cbobuyer.Items.Add("Others")
    End Sub

    Private Sub btntotal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btntotal.Click
        nobooks = Val(txtbooks.Text)
        If cbobooktype.Text = "Mathematics" Then
            cost = 600
        ElseIf cbobooktype.Text = "Marketing" Then
            cost = 350
        ElseIf cbobooktype.Text = "Accounting" Then
            cost = 652
        ElseIf cbobooktype.Text = "Economics" Then
            cost = 510
        Else
            cost = 350
        End If
        If cbobuyer.Text = "Student" Then
            discount = 65
        ElseIf cbobuyer.Text = "Teacher" Then
            discount = 85
        Else
            discount = 40
        End If
        total = (nobooks * cost) - (nobooks * discount)

        lbltotal.Text = "Rs." & "" & FormatNumber(total)
    End Sub


    Private Sub btnclear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnclear.Click
        cbobooktype.Text = ""
        cbobuyer.Text = ""
        txtbooks.Text = ""
        lbltotal.Text = ""

    End Sub

    Private Sub btnexit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnexit.Click
        Me.Close()
    End Sub
End Class

OP: