Lab 01 - Source Code Reference

PVFC ASP.NET Web Forms - Layered Architecture (PVFC_DataLayer + PVFC_WebApp)

Table of Contents

• Registration.aspx.vb
• Order.aspx.vb
• Search.aspx.vb
• Catalog.aspx.vb
• Payment.aspx.vb
• Login.aspx.vb

Registration.aspx.vb - New Customer Registration

Uses CustomerRepository from PVFC_DataLayer to insert the customer.

Imports PVFC_DataLayer

Public Partial Class Registration
    Inherits System.Web.UI.Page

    Protected Sub btnRegister_Click(ByVal sender As Object, ByVal e As EventArgs)
        If Not Page.IsValid Then Return

        Dim fullName As String = (txtFirstName.Text.Trim() & " " & txtLastName.Text.Trim()).Trim()
        Dim customerId As Integer

        If Not Integer.TryParse(txtCustomerId.Text.Trim(), customerId) Then
            lblMessage.Text = "Error: Customer ID must be a number."
            lblMessage.Visible = True
            Return
        End If

        Try
            ' Delegates to PVFC_DataLayer.CustomerRepository
            CustomerRepository.AddCustomer(customerId, fullName, txtAddress.Text.Trim(), txtCity.Text.Trim(), txtState.Text.Trim().ToUpper(), txtPostalCode.Text.Trim())
            lblMessage.Text = "Success: Customer " & fullName & " registered! (ID: " & customerId & ")"
            lblMessage.Visible = True
            ClearForm()
        Catch ex As SqlException
            Dim msg As String = If(ex.Number = 2627, "A customer with ID " & customerId & " already exists.", ex.Message)
            lblMessage.Text = "Error: " & msg
            lblMessage.Visible = True
        End Try
    End Sub

    Private Sub ClearForm()
        txtCustomerId.Text = ""
        txtFirstName.Text = ""
        txtLastName.Text = ""
        txtAddress.Text = ""
        txtCity.Text = ""
        txtState.Text = ""
        txtPostalCode.Text = ""
    End Sub
End Class
    

Order.aspx.vb - Order Placement

Uses OrderRepository and ProductRepository from PVFC_DataLayer. OrderLine class stored in ViewState.

Imports PVFC_DataLayer

Public Partial Class Order
    Inherits System.Web.UI.Page

    Private Const VS_LINES As String = "OrderLines"

    Private ReadOnly Property Lines As List(Of OrderLine)
        Get
            If ViewState(VS_LINES) Is Nothing Then ViewState(VS_LINES) = New List(Of OrderLine)()
            Return DirectCast(ViewState(VS_LINES), List(Of OrderLine))
        End Get
    End Property

    Protected Sub btnAddToOrder_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim productId As Integer = Integer.Parse(ddlProducts.SelectedValue)
        Dim qty As Integer = 1
        Integer.TryParse(Request.Form("txtQtySelect"), qty)

        ' Calls PVFC_DataLayer.ProductRepository.GetProductById()
        Dim row As DataRow = ProductRepository.GetProductById(productId)
        If row Is Nothing Then Return

        Dim existing As OrderLine = Lines.Find(Function(ln) ln.ProductId = productId)
        If existing IsNot Nothing Then
            existing.Qty += qty
        Else
            Lines.Add(New OrderLine With {.ProductId = productId, .ProductName = row("Product_Description").ToString(), .UnitPrice = Convert.ToDecimal(row("Standard_Price")), .Qty = qty})
        End If
        RefreshOrderLines()
    End Sub

    Protected Sub btnPlaceOrder_Click(ByVal sender As Object, ByVal e As EventArgs)
        If Lines.Count = 0 Then Return
        Dim custId As Integer = Integer.Parse(txtCustomerId.Text.Trim())
        Dim orderId As Integer = OrderRepository.GetNextOrderId()
        Dim productIds As Integer() = Lines.Select(Function(ln) ln.ProductId).ToArray()
        Dim quantities As Integer() = Lines.Select(Function(ln) ln.Qty).ToArray()
        Try
            ' PVFC_DataLayer.OrderRepository handles SQL Transaction internally
            OrderRepository.PlaceOrder(orderId, custId, DateTime.Parse(txtOrderDate.Text), productIds, quantities)
            lblMessage.Text = "Order #" & orderId & " placed successfully!"
            lblMessage.Visible = True
            ClearAll()
        Catch ex As Exception
            lblMessage.Text = "Error: " & ex.Message
            lblMessage.Visible = True
        End Try
    End Sub
End Class

<Serializable>
Public Class OrderLine
    Public Property ProductId As Integer
    Public Property ProductName As String
    Public Property UnitPrice As Decimal
    Public Property Qty As Integer
End Class
    

Search.aspx.vb - Product Search

Imports PVFC_DataLayer

Public Partial Class Search
    Inherits System.Web.UI.Page

    Protected Sub btnSearch_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim term As String = txtSearch.Text.Trim()
        Dim lineId As String = ddlLineFilter.SelectedValue

        ' Delegates to PVFC_DataLayer.ProductRepository
        Dim dt As DataTable = ProductRepository.SearchProducts(term, lineId)
        gvResults.DataSource = dt
        gvResults.DataBind()
        lblCount.Text = "Found " & dt.Rows.Count & " item(s)."
    End Sub
End Class
    

Catalog.aspx.vb - Product Catalog CRUD (Admin)

Imports PVFC_DataLayer

Public Partial Class Catalog
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
        If Not IsPostBack Then BindGrid()
    End Sub

    Private Sub BindGrid()
        gvCatalog.DataSource = ProductRepository.GetAllProducts()
        gvCatalog.DataBind()
    End Sub

    Protected Sub gvCatalog_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
        Dim productId As Integer = Convert.ToInt32(gvCatalog.DataKeys(e.RowIndex).Value)
        Dim description As String = DirectCast(gvCatalog.Rows(e.RowIndex).Cells(1).Controls(0), TextBox).Text
        Dim price As Decimal = Convert.ToDecimal(DirectCast(gvCatalog.Rows(e.RowIndex).Cells(3).Controls(0), TextBox).Text)
        ProductRepository.UpdateProduct(productId, description, price)
        gvCatalog.EditIndex = -1
        BindGrid()
    End Sub

    Protected Sub gvCatalog_RowDeleting(ByVal sender As Object, ByVal e As GridViewDeleteEventArgs)
        Dim productId As Integer = Convert.ToInt32(gvCatalog.DataKeys(e.RowIndex).Value)
        ProductRepository.DeleteProduct(productId)
        BindGrid()
    End Sub
End Class
    

Payment.aspx.vb - Payment Lookup and Processing

Imports PVFC_DataLayer

Public Partial Class Payment
    Inherits System.Web.UI.Page

    Protected Sub btnLookup_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim orderId As Integer = Integer.Parse(txtOrderId.Text.Trim())
        Dim amount As Decimal = OrderRepository.GetOrderTotal(orderId)
        txtTotalAmount.Text = amount.ToString("F2")
    End Sub

    Protected Sub btnPayment_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim orderId As Integer = Integer.Parse(txtOrderId.Text.Trim())
        Dim amount As Decimal = Decimal.Parse(txtTotalAmount.Text)
        OrderRepository.RecordPayment(orderId, amount)
        lblMessage.Text = "Payment of $" & amount.ToString("N2") & " recorded for Order #" & orderId & "."
        lblMessage.Visible = True
    End Sub
End Class
    

Login.aspx.vb - Session-based Login

Public Partial Class Login
    Inherits System.Web.UI.Page

    Protected Sub btnLogin_Click(ByVal sender As Object, ByVal e As EventArgs)
        If txtUsername.Text = "Admin" AndAlso txtPassword.Text = "Admin123" Then
            Session("Username") = txtUsername.Text
            Session("IsAdmin") = True
            Response.Redirect("Default.aspx")
        Else
            lblMessage.Text = "Invalid credentials."
            lblMessage.Visible = True
        End If
    End Sub
End Class