Imports System
Imports System.ComponentModel
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports Microsoft.SharePoint
Imports Microsoft.SharePoint.WebControls

<ToolboxItemAttribute(false)> _
Public Class MyFirstWebPart
    Inherits WebPart

    Dim lblUserEntry As Label = New Label
    Dim txtbxUserEntry As TextBox = New TextBox
    Dim lblFinalCost As Label = New Label
    Dim txtbxFinalCost As TextBox = New TextBox
    Dim btnCalcTax As Button = New Button
    Dim totalTax As Double = 0.0
    Dim prodTax As Double = 0.11


    Protected Overrides Sub CreateChildControls()

        lblUserEntry.Text = "Cost of Widget:"
        lblFinalCost.Text = "Final Cost:    "
        btnCalcTax.Text = "Calc."
        txtbxUserEntry.Text = "59.30"

        Me.Controls.Add(lblUserEntry)
        Me.Controls.Add(txtbxUserEntry)
        Me.Controls.Add(New LiteralControl("<p>"))
        Me.Controls.Add(lblFinalCost)
        Me.Controls.Add(txtbxFinalCost)
        Me.Controls.Add(New LiteralControl("<p>"))
        Me.Controls.Add(btnCalcTax)

        'From c#: btnCalcTax.Click += new EventHandler(btnCalcTax_Click)
        AddHandler btnCalcTax.Click, AddressOf btnCalcTax_Click

        'From c#: Base.CreateChildControls()
        MyBase.CreateChildControls()

    End Sub

    Private Sub btnCalcTax_Click(ByVal sender As Object, ByVal e As EventArgs)

        Dim prodCost As Double = Convert.ToDouble(txtbxUserEntry.Text)
        totalTax = Math.Round(prodCost - (prodCost * prodTax), 2) * 100 / 100
        txtbxFinalCost.Text = totalTax.ToString

    End Sub