Introduction

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Lessons

W1: Intro / Lab

W2: Ch1 / Lab

W3: Ch2a/ Lab

W4: Ch2b/ Lab

W5: Lab/ Lab

W6: Lab/ Lab

W7: Ch3/ Lab

W8: Ch4/Lab

W9: Ch5/Exam

W10:Ch6/Lab

W11:Ch7/Lab

W12:Pres/Lab

W13:Ch8/Lab

W14:Lab/Lab

W15:Pres/Pres

Introduction

Dynamic Page Handout

Dynamic pages interact with the user. Examples include games, order forms, and shopping carts.

Scripts

Common to many dynamic website technologies is the use of scripts

Examples include JavaScript (Netscape), and VBScript (Microsoft)

Scripts are interpreted, not compiled and are simpler and easier to learn than programming

Examples

change a formatted date on a page

cause a linked to page to appear in a popup window

cause text or graphic image to change during a mouse rollover

Can be written for either the client or the server

Run on many different platforms (Mac, UNIX, Windows) with few changes

JavaScript

Example tag: <script language= “JavaScript”>

Developed by Netscape

Most common

Not Java (Java is a complete programming language)

VBScript

Microsoft’s scaled down version of Visual Basic for scripting

Security issues discussed later

Web resources: http://www.ecma.ch http://javascirpt.internet.com http://www.vbscripts.com

Client Side

Scripts

Interpreted within the web browser; a part of the page, browser sends script to script engine

International standard ECMA-262

Advantages and disadvantages

Applets

A Java program (Java is a compiled OOP) that runs within a Web page; example tutorial clock

Controls and form fields can control and assign values for applet use

Applets can do essentially everything JavaScript can do, and much more

Web resources: www.gamelan.com

Advantages and disadvantages

Server Side

Scripts

Results of script sent to server then on to client’s browser

Source code does not appear in browser

No standard, Netscape supports JavaScript on NES; Microsoft supports Jscript and VBS on IIS.

Server Side Include Files

Frequently used server side scripts contained in a file separate from the webpage using them

Permits reuse of code for multiple web pages.

Example: inserting last modified statement (or other environmental variables) into the html

before sending it to the client’s browser.

Advantages and disadvantages

ASP

Indicated by .asp extensions

Server side scripting plus interaction with databases, customized emails from web pages, detects

browser capabilities, reads and writes to file system

Uses scripts such as VBScript or Jscript, and also ActiveX Data Objects (ADOs)

Advantages and disadvantages

CGI Common Gateway Interface

A standard way for server to pass user’s request to an application program and receive data back to

forward to the user.

Example

the server at mybiz.com would pass control to the CGI application called formprog.pl to

record the enter data and return a confirmation message. pl is the extension for Perl (Perl,

powerful, easy to learn, and free is the most widely used CGI scripting language; other

common languages for applications are C, C++, Java)

Supported by all servers

Advantages and disadvantages

Cold Fusion

Tag based

Easy to learn

Web resources: www.systemanage.com/cff/webring.html www.macromedia.com/support/coldfusion/

Advantages and disadvantages

Cascading Style Sheets

Separates content and style; a set of style rules is called a style sheet

Server can provide a style sheet that matches display device (PC, hand set, etc.)

Applying a number of different style sheets to the same document gives “cascading” its name

Not well supported by Netscape through 4.75

Display tags can double the size of an average htm document, standardization hard

Example: <h1 align=“center”><font color=“green”>Heading Text</font></h1>

With CSS: H1{color: green; text-align: center;}

Style tags <style> can be included in head section and only affect that document

Or style sheets in external document lets you specify rules for different HTML documents

Example: <link href=“styles.css” rel=“stylesheet”>