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CS 131 Wrap Up
Fall 2008
What Good is Programming?
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What have you learned?
Dataint
float
char
bool
string
array
struct
arrays of struct
Controlsequential
loop (for, while, while/do)
selection (if, switch)
Organizationfunctions
libraries
Is there anything you can't represent now? yes, more complicated information structures in CS 132
Are functions enough to organize a program? no, we need better ways to encapsulate related functionality
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Who Needs This?
Programming underlies most of what you do
In your worldStreams are fancier
input: mouse, touchpad, laser trigger, voice
output: webpage, pda display, cellphone
Information organization and its exploitation are less visible
do you ever ask how your cellphone knows who has called?
how can find a recipe for crab cakes on the web?
You function at a higher level
Photoshop commands versus processing an array
Google instead of a programming a search
But the underlying programming is what you have learned
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What else is Computer Science?
Database management
how can Amazon find all books by a given author?
how do they know what to suggest you buy?
Web programming
how does their website work so flawlessly?
Software engineering
how is a million line program developed?
Graphics
how can a program rotate an object in 3d?
how can Flash transform one object into another?
Computer engineering
who is building the next generation of computers and gadgets?
IT management
Wells should have wifi everywhere and the net always up, right?
Communications
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Where is Programming on the Web?
HTML for static web pages
JavaScript for client-side programmingthe sayings at the bottom of my page
Towers of Hanoi
PHP/ASP/Perl for server-side programminginterfaces to databases
interfaces to other web services such as credit card processing
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Client(you)
Server(aurora.wells.edu)
(2)
Client SW(IE/Netscape/
Firefox)
Server SW(Apache, IIS)
(1)
(3)
Steps: (1) Client sends an HTTP* request message (clicks on a link) (2) Server processes the request (3) Server sends response (an HTML page) (4) Client browser interprets it
* Hypertext Transfer Protocol, a format for Internet messages
Client/Server Communication (HTML)
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Example: HTML (a markup language to define how to format the content)
<html>
<head>
<title>Wells Open House</title>
</head>
<body>
<h1>Welcome to Wells</h1>
Things to do
<ol>
<li>Take a tour</li>
<li>Go to a class</li>
<li>Eat lunch</li>
</ol>
</body>
</html>
The page: welcome.htm
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)
(2)
Client(you)
Server(e.g. aurora)
Client SW (Netscape/IE/
Firefox)
(1)
(2)
Steps: (1) Client sends HTTP request message (2) Server sends page back to the client (3) Client executes JavaScript commands that are in the page
Client-Side Programming (JavaScript)
JavaScript interpreter
Server SW(IIS,
Apache)
(3)
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Example: JavaScript
<html>
<head> <title>Simple Alert</title>
</head>
<body>
Pick the right door and win a car:
<form>
<input type="button" value="Door 1"
onclick="alert('You got my goat')">
<input type="button" value="Door 2"
onclick="alert('You win a car')">
</form>
</body>
</html>
The page: door.htm
Other examples: checking form input, sudoku
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)
(2)
Client(you)
Server(e.g. my computer)
Client SW (Netscape/IE/
Firefox)
(1)
(3)
Steps: (1) Client sends HTTP request message (2) Server processes request message and executes any client-side programming (e.g. a database interaction) (3) Server sends page back to the client
Server-Side Programming (PHP)
CGI program
JavaScript interpreter CGI
Interface
Server SW(IIS,
Apache)
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Server-Side Programming
• Uses resources that are not on the client computer– a databaseof records
– software for processing them
• Languages commonly used: Perl, ASP, PHP
• Other applications– process an online order
– check the weather
– find driving directions to Wells
– manage your Facebook information
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<?php require_once('Connections/cn330.php');
mysql_select_db($database_cn330, $cn330);
$query_rsUsers = "SELECT * FROM tblUser";
$rsUsers = mysql_query($query_rsUsers, $cn330);
$row_rsUsers = mysql_fetch_assoc($rsUsers);
?>
<html><head><title>Write User Names</title></head><body>
<h2> Display All User Names</h2>
<br />
<?php
do {
echo $row_rsUsers['FullName'];
?>
<br />
<?php
} while ($row_rsUsers = mysql_fetch_assoc($rsUsers));
?>
</body></html> (view the code sent to the browser)
Example: PHP (WriteNames1.php)
