Cookies

1
Cookies

• Cookies are bits of software placed on the client
  machine when browsing web site.
• Its a text file !
• Cookies are a used for
• Customizing user experience
• Maintain use information

2
Cookies in ASP/VBScript

• In Microsoft ASP/VBScript, there are methods and
  instance variables in the request and response
  objects dedicated to the handling of cookies.
• Before using these, it is important to note that
  the ASP/VBScript associate a name with a cookie.

3
Cookies in ASP/VBScript

• Setting a cookieIt is necessary to invoke the
  cookies instance variable of the response object
  with 1. String valued parameter
  (name) 2. Assign suitable value to the variable.
• Response.cookies(visits) 1

4
Cookies Collection
5
Cookies Collection
6
Example 1 Code

• lt CheckCookie request.cookies("Example")
• If CheckCookie "" Then
• response.cookies("Example").expires date 7
• response.cookies("Example") "eyhab almasri"
• response.write("Cookie created")
• Else
• name request.cookies("Example")
• response.write(name)
• End If
• gt

7
Cookie Expiration

• The expires simply specifies when the browser may
  discard the cookie from its permanent location.
• It is usually used to set the time period for
  which a persistent cookie is stored.
• It is set to an absolute date.
• If the date specified is earlier than today, the
  cookie is immediately discarded.
  response.cookies("route").expires date 1
• Date is an ASP/VBScript internal variable.

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Examples Demo 1

• lt CheckCookieA request.cookies("Example1")
• CheckCookieB request.cookies("Example2")
• If CheckCookieA "" Then
• response.cookies("Example1").expires Now() 1
• response.cookies("Example1")("Name") "Eyhab
  Al-Masri"
• response.write("Created Cookie A" "ltbrgt")
• Else
• response.write("Cookie A returned" "ltbrgt")
• response.write("Hello " request.cookies("Exampl
  e1")("Name") " ! Welcome backltbrgt")
• End If
• gt
• ltbrgtltbrgt
• lt
• If CheckCookieB "" Then
• response.cookies("Example2").expires Now() 1
• response.cookies("Example2")("Major")
  "Computer Science"
• response.write("Created Cookie B" "ltbrgt")
• Else
• response.write("Cookie B returned" "ltbrgt")

9
Examples Demo 2

• lt CheckCookieA request.cookies("Example1")
• CheckCookieB request.cookies("Example2")
• If CheckCookieA "" Then
• response.cookies("Example1").expires Now() 1
• response.cookies("Example1")("Name") "Eyhab
  Al-Masri"
• response.write("Created Cookie A" "ltbrgt")
• Else
• response.cookies("Example1") ""
• End If
• gt
• ltbrgtltbrgt
• lt
• If CheckCookieB "" Then
• response.cookies("Example2").expires Now() 1
• response.cookies("Example2")("Major")
  "Computer Science"
• response.write("Created Cookie B" "ltbrgt")
• Else
• response.write("Cookie B returned" "ltbrgt")
• response.write("Major is " request.cookies("Exa
  mple2")("Major") "ltbrgt")

10
Sessions

• How do you keep user-specific information while a
  user navigates through the site?
• Session object represents the current users
  session on the web server
• User specific
• Properties and methods allow for information
  manipulation

11
Sessions

• Web servers identifies each user session with a
  unique session ID
• Demo 1
• You can create other session variables and
  customize the session based on your needs.
• Sessions are important in maintaining information
  about users.

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Sessions

• Properties
• CodePage (character set)
• LCID (formatting dates)
• SessionID (unique identifier)
• Timeout (length in minutes for keeping session
  alive, def 20 mins)
• Collections
• Contents
• StaticObjects
• Methods
• Abandon (releases memory used by web server for
  sessions)
• Events
• Session_OnEnd
• Session_OnStart

13
Why use Databases

• Small, medium an large-sized business use
  databases to track inventory, employees, etc.
• Explosion of the internet.
• Increase profitsmanaging-creating-and delivery
  information over the web.

14
Databases

• A Database is a collection of facts that are
  systematically organized (Ashenfelter 1999) it
  is an information container.
• Most common type of databases is the relational
  databases.
• It usually consists of the following objects
  Tables, Queries, Forms, and Reports.

15
Databases

• TablesData is stored in tables, as records of
  information related to a single subject. Records
  store pieces of information as fields, and Each
  field may have a specific data type associated
  with it.

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Databases

• Queriesare general-purpose utility tools such
  as deleting/updating specific records.
• Forms-The user interface of database
  applications -Generally accessed directly
  (adding, editing, deleting, or searching for
  individual records)
• Reportsprinting specific records or group of
  records for specific purposes

17
Relational Databases

• By using a common identifier between tables it is
  possible to "relate" one table to another.
• ScenarioFor instance, imagine you had a table
  that contained data about items sold in a store
  today.
• You also have tables that give you the details
  about the items and the vendors that sell them to
  you.

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Primary Key

• Valid Tablesmust have one field with values
  that are NOT the same for two different
  records.This is what is called Primary Key for
  that table.
• These fields are used to link or relate tables
  to each other.

19
Relationships

• Microsoft Access is a relational databaseall
  data can be stored in one database file where the
  file can contain multiple tables with defined
  relationships between the tables.
• In previous example, we used to store teacher
  information