1. Web Application with Database
CS 3870/CS 5870: Note05
Prog3
Web Application with Database

2. Master Page All Web pages will be similar
Should be created before other web pages
Add New Items
Master Page
Name: Prog3MasterPage.master
Check “Place code in separate file”
Uncheck “Select master page”
Could create a master page based on another master page
May be incomplete and need to come back later

3. Elements on the Master page
External CSS file
<link href="StyleSheet.css" rel="stylesheet" type="text/css" />
Form
All controls should be inside Form for dynamic pages
Two ContentPlaceHolder controls: could change id
<asp:ContentPlaceHolder id="head" runat="server">
</asp:ContentPlaceHolder>
<asp:ContentPlaceHolder id="ContentPlaceHolder1"
runat="server">

4. Elements on the Master page
Leave ContentPlaceHolder empty
Add all common elements before/after ContentPlaceHolder
Title and Names
Adding navbar: incomplete

5. Content Pages Create the three pages using the master page
Add New Item
Web Form
Place code in separate file
Select master page
Add
Select folder
Select Master page
The second web form
Web Form (with master)

6. Content Pages No Form control on content pages Two Content controls
The form control on the master page will be combined with the controls on the content page
Two Content controls
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server"> </asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="Prog3Body" Runat="Server">
</asp:Content>
Type it if not there

7. Complete the Navbar on Master Page
<ul class="navbar">
<li> <a href="Default.aspx"> All Products </a></li>
<li> <a href="Updating.aspx"> Updating Products </a></li>
<li> <a href="Shopping.aspx"> Shopping </a></li>
</ul>
Type and select the pages.

8. Adding Elements
Type “All Products”, “Updating” and “Shopping” on the three pages
Run IE to see the pages

9. The Database UWPCS3870 SQL Server on Alpha User: MSCS
(not case sensitive)
Password: MasterInCS
(case sensitive)

10. Table Product
Four Columns ProductID : nchar(4), primary key, not updatable ProductNmae: nvarchar(50) UnitPrice : smallmoney Description : nvarchar(MAX), allow nulls

11. Accessing Database Data Source Controls Code class Prog3 SqlDataSource
AccessDataSource
. . .
Code class
Connection
Command
DataAdpater
AdapterBuilder
Prog3
Use Code class

12. ASP.NET Folders Solution Explorer Right click Web site
Add ASP.NET Folder
App_Code
(App_Data)
. . .

13. SQLDataClass Code class in folder App_Code No code module
All variables and procedures should be
Shared (Static in C#, Java and C++)
Otherwise, need to create object

14. The objects are available all the times.
Variables
Public Class SQLDataClass
Private Const ConStr As String = "Data Source=Alpha;” &
“Initial Catalog=UWPCS3870;Persist Security Info=True;” &
“User ID=MSCS;Password=MasterInCS"
Private Shared prodAdapter As System.Data.SqlClient.SqlDataAdapter
Private Shared prodBuilder As System.Data.SqlClient.SqlDataAdapter
Private Shared prodCmd As New Data.SqlClient.SqlCommand
Private Shared con As New Data.SqlClient.SqlConnection
Public Shared tblProduct As New Data.DataTable("Product")
. . .
End Class
The objects are available all the times.

15. Setup Command and Adapter
‘ Sets up the connection, command and adapter Public Shared Sub setupProdAdapter() con.ConnectionString = ConStr prodCmd.Connection = con prodCmd.CommandType = Data.CommandType.Text prodCmd.CommandText = "Select * from Product order by ProductID" prodAdapter = New System.Data.SqlClient.SqlDataAdapter(prodCmd) prodAdapter.FillSchema(tblProduct, Data.SchemaType.Source) End Sub

16. Retrieve Data Records
‘ Gets the table records and the table schema Public Shared Sub getAllProducts() ‘ Need to reset the command prodCmd.CommandText = "Select * from Product order by ProductID" Try If Not tblProduct Is Nothing Then tblProduct.Clear() End If prodAdapter.Fill(tblProduct) Catch ex As Exception Throw ex Finally con.Close() End Try End Sub

17. Setting up the Adapter
‘ Global.asax Sub Application_Start(. . .) SQLDataClass.setupProdAdapter() End Sub Do it just once for the application for all sessions of all users.

18. Setting up the Adapter Public Shared Sub getAllProdcts()
If prodAdapter Is Nothing Then
setupProdAdapter()
End If
prodCmd.CommandText = "Select * from Product order by ProductID"
Try
. . .
End Try
End Sub

19. Binding Gridview
‘ Add a GridView on page Default.aspx ‘ GridView: ToolBox – Data Protected Sub Page_Load(. . .) Handles Me.Load SQLDataClass.getAllProducts() GridView1.DataSource = SQLDataClass.tblProduct GridView1.DataBind() End Sub Refill the data table for each page request.

20. Formatting GridView
<asp:GridView runat="server" ID="GridView1" AutoGenerateColumns="False" style="z-index: 1; position: relative; width: 50%; margin-left:25%; align-items: center; height: 176px" > <Columns> <asp:BoundField DataField="ProductID" HeaderText="Product ID" > <ItemStyle HorizontalAlign="Center" Width="10%"></ItemStyle></asp:BoundField> <asp:BoundField DataField="ProductName" HeaderText="Product Name" > <ItemStyle HorizontalAlign="Left" Width="20%"></ItemStyle></asp:BoundField> <asp:BoundField DataField="UnitPrice" HeaderText="Unit Price" DataFormatString="{0:c}" HtmlEncode="False" > <ItemStyle HorizontalAlign="Right" Width="10%"></ItemStyle></asp:BoundField> <asp:BoundField DataField="Description" HeaderText="Description"> <ItemStyle HorizontalAlign="right" Width="10%"></ItemStyle></asp:BoundField> </Columns> </asp:GridView>

21. Page Updating Display record one at a time
Display the first record for the first visit
Display the same record for return visit
Need Session variable
Begin with “Prog3_”

22. Session Variables
Sub Session_Start(. . .) Session(“Prog3_Index”) = 0 End Sub Protected Sub Page_Load(…) Handles Me.Load DisplayRow(Session("Prog3_Index"))

23. Display Record
Protected Sub Page_Load(…) Handles Me.Load DisplayRow(Session(“Prog3_Index”)) End Sub Private Sub DisplayRow(Index As Integer) Dim row As Data.DataRow row = SQLDataClass.tblProduct.Rows(index) ‘ May need formatting txtID.Text = row(0) txtName.Text = row(1) txtPrice.Text = row(2) txtDescription.Text = row(3)

24. Navigation Buttons
Partial Class Prog3_Updating Protected Sub Button6_Click(…) Handles btnNext.Click Session(“Prog3_Index”) += 1 DisplayRow(Session(“Prog3_Index”)) End Sub Protected Sub Button6_Click(…) Handles btnPrevious.Click Session(“Prog3_Index”) -= 1

25. Enable/Disable Buttons
Could make a private Sub. Your choice.

26. Navigation Buttons
Partial Class Prog3_Updating Protected Sub Button6_Click(…) Handles btnNext.Click Session(“Prog3_Index”) += 1 DisplayRow(Session(“Prog3_Index”)) EnableDisableButtons() End Sub Protected Sub Button6_Click(…) Handles btnPrevious.Click Session(“Prog3_Index”) -= 1

27. Enable/Disable Buttons
Sub EnableDisableButtons() if Session(“Prog3_Index”) = 0 Then ElseIf Session(“Prog3_Index") = SQLDataClass.tblProduct.Rows.Count - 1 Then Else End If End Sub

28. SQL Statements
Update Product Set ProductName = ‘NewName’, UnitPrice = newPrice Description = ‘NewDescription’, Where ProductID = ‘theID’; Insert Into Product Values(‘ID’, ‘Name’, Price, ‘Description’); Delete From Product

29. Button Update
‘ Page Updating.Aspx ‘ID not to be modified Protected Sub Button6_Click(…) Handles btnUpdate.Click ‘Dim theID As String = txtID.Text Dim oldID As String = SQLDataClass.tblProduct.Rows(Session(“Prog3_Index"))(0) Dim newName As String = txtName.Text Dim newPrice As Double = txtPrice.Text Dim newDesc As String = txtDesc.Text SQLDataClass.UpdateProduct(theID, newName, newPrice, newDesc) End Sub

30. UpdateProduct
‘ SQLDataClass Public Shared Sub UpdateProduct(theID As String, newName As String, newPrice As Double, newDesc As String) ‘ Building SQL statement with variables prodCmd.CommandText = ". . ." Try con.Open() prodCmd.ExecuteNonQuery() Catch ex Throw ex Finally con.Close() End Try End Sub

31. UpdateProduct
‘ SQLDataClass Public Shared Sub UpdateProduct(theID As String, newName As String, newPrice As Double, newDesc As String) prodCmd.CommandText = " Update Product" & _ " Set ProductName = ‘newName', " & _ " UnitPrice = newPrice, " & _ " Description = ‘newDesc'" & _ " Where ProductID = 'theID‘” Try End Try End Sub Incorrect!

32. UpdateProduct ‘ SQLDataClass
Public Shared Sub UpdateProduct(theID As String,
newName As String, newPrice As Double)
‘ Building SQL statement with variables
prodCmd.CommandText =
" Update Product " & _
" Set ProductName = " & newName & “, " & _
" UnitPrice = " & newPrice & ", " & _
" Description = " & newDesc & _
" Where ProductID = " & theID
Try
. . .
End Try
End Sub
Incorrect!

33. UpdateProduct ‘ SQLDataClass
Public Shared Sub UpdateProduct(theID As String,
newName As String, newPrice As Double)
‘ Building SQL statement with variables
prodCmd.CommandText =
" Update Product " & _
" Set ProductName = '" & newName & "'," & _
" UnitPrice = " & newPrice & ", " & _
" Description = '" & newDesc & "'" & _
" Where ProductID = '" & theID & "'“
Try
. . .
End Try
End Sub
Correct!

34. Try-Catch-Finally
Public Shared Sub UpdateProduct(oldID As String, newID As String, newName As String, newPrice As Double) prodCmd.CommandText = ". . ." Try con.Open() prodCmd.ExecuteNonQuery() ‘ update database Catch ex Throw new Exception(ex.Message & “ ” & prodCmd.CommandText) Finally con.Close() ‘ always close it End Try End Sub

35. Button Update
‘ Page Updating.Aspx Protected Sub Button6_Click(…) Handles btnUpdate.Click Dim Try DataClass.UpdateProduct(theID, newName, newPrice, newDesc) txtMsg.Text = "Record updated“ ‘ must update tblProducts SQLDataClass.getAllProduct() Catch ex txtMsg.Text = ex.Message ‘including myCmd.CommandText End Try End Sub

36. Cannot Update Correctly!
Updating
‘ Page Updating.Aspx
Partial Class Prog3_Updating
Inherits System.Web.UI.Page
Protected Sub Page_Load(. . .) Handles Me.Load
txtMsg.Text = ""
DisplayRow(Session(“Prog3_Index"))
End Sub
Cannot Update Correctly!

37. Cannot Update Correctly!
Updating
Partial Class Prog3_Updating
Inherits System.Web.UI.Page
Protected Sub Page_Load(. . .) Handles Me.Load
txtMsg.Text = ""
DisplayRow(Session(“Prog3_Index"))
End Sub
Cannot Update Correctly!
Post Back!

38. PostBack Partial Class Prog3_Updating Inherits System.Web.UI.Page
Protected Sub Page_Load(. . .) Handles Me.Load
txtMsg.Text = “”
If Not IsPostBack Then
DisplayRow(Session(“Prog3_Index"))
Else
‘ Do not do anything
‘ Textboxes keep their values from client
End If
End Sub

39. PostBack Partial Class Prog3_Updating Inherits System.Web.UI.Page
Protected Sub Page_Load(. . .) Handles Me.Load
txtMsg.Text = “”
‘ Else is not needed
If Not IsPostBack Then
DisplayRow(Session(“Prog3_Index"))
End If
End Sub

40. Buttons
btnNew
New
Save New
btnDelete
Delete
Cancel
Enabled/Disabled