Mark Dixon, SoCCE SOFT 131Page 1 23 – Web applications: Databases & ASP

Mark Dixon, SoCCE SOFT 131Page 2 Session Aims & Objectives Aims –To introduce the fundamental ideas involved in using server-side code to read data from databases Objectives, by end of this week’s sessions, you should be able to: –create an ASP web page that displays data read from a database

Mark Dixon, SoCCE SOFT 131Page 3 People Database IDSurnameForenamesPhone 1DixonMark SmithJohn JonesSally BloggsFred AndersonGenny01752

Mark Dixon, SoCCE SOFT 131Page 4 People: Specification User requirement: –Display list of people from database online How: –Combine our knowledge of: ASP (active server pages) – covered in week 21 ADO (activeX data objects) – covered in week 17

Mark Dixon, SoCCE SOFT 131Page 5 People.asp Example: People Personal Address Book Personal Address Book <% Const cs = " Provider=…;Data Source=D:\People.mdb; " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs

Mark Dixon, SoCCE SOFT 131Page 6 Example: People (recordset 1) Personal Address Book Personal Address Book <% Const cs = " … " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs Dixon

Mark Dixon, SoCCE SOFT 131Page 7 Example: People (recordset 2) Personal Address Book Personal Address Book <% Const cs = " … " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs Dixon Smith

Mark Dixon, SoCCE SOFT 131Page 8 Example: People (recordset 3) Personal Address Book Personal Address Book <% Const cs = " … " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs Dixon Smith Jones

Mark Dixon, SoCCE SOFT 131Page 9 Example: People (recordset 4) Personal Address Book Personal Address Book <% Const cs = " … " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs Dixon Smith Jones Bloggs

Mark Dixon, SoCCE SOFT 131Page 10 Example: People (recordset 5) Personal Address Book Personal Address Book <% Const cs = " … " Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs Do Until rs.EOF Response.Write rs.Fields("Surname").Value Response.Write " " rs.MoveNext Loop rs.Close Set rs = Nothing %> rs Dixon Smith Jones Bloggs People.asp Anderson

Mark Dixon, SoCCE SOFT 131Page 11 Person: Specification User requirement: –Display person’s details from database online, and be able to move to next and previous person (record) Problem: –Can’t use.MoveNext and.MovePrev recordset methods: record set does not persist between pages

Mark Dixon, SoCCE SOFT 131Page 12 Example: Person (html) Person's Details Person's Details <% ' ASP code will go here (next slide). %> Person.asp Self post

Mark Dixon, SoCCE SOFT 131Page 13 Example: Person (ASP) <% Const adOpenDynamic = 3 Const cs = "…" Dim rs Set rs = CreateObject("ADODB.Recordset") rs.Open "Person", cs, adOpenDynamic If Session("curID") <> "" Then rs. Find "[ID] = " & Session("curID") If Request.Form("btnPrev") <> "" Then rs. MovePrevious ElseIf Request.Form("btnNext") <> "" Then rs. MoveNext End If Session("curID") = rs.Fields("ID").Value Response.Write rs.Fields("Surname").Value & " " Response.Write rs.Fields("Forenames").Value rs.Close Set rs = Nothing %> Button value empty unless button was pressed Use session variable to record current position in db