PHP

1
PHP

• A Server Side Programming Language

2
PHP The Good

• Easy to develop and deploy
• Excellent Documentation
• http//www.php.net
• PHP powers some successful projects
• Mediawiki
• Wordpress
• Drupal
• Joomla
• Moodle

3
PHP The Bad

• Extremely loose structure invites sloppy coding.
• PHP was designed to add programming logic to HTML
  pages this muddies the view and controller
  layers of your application

4
PHP
php code to be executed before document is
served to the client
5
PHP

• Files have a .php extension
• Are not complied
• Are stored in your web servers document tree
• .php files are parsed by the php engine before
  they are sent to the client
• Code between is computed and the
  resulting text is sent to the client

6
Variables

• Almost always local
• Implicitly Typed
• Variables can be forced to a data type
• http//www.php.net/manual/en/language.types.type-j
  uggling.php

7
Variables

• Superglobals
• Contain system information
• Are pre-named (reserved)
• Start with _
• _GLOBALS
• _SERVER
• _POST
• _FILES
• _COOKIE
• _SESSION
• _REQUEST
• _ENV

8
_GET

• Array of variables passed to the script with the
  query string

Get request
Query string
php code prints out the value of var1in this
case stuff
9
_POST

• Array of form data posted to your script
• Example file http//www.rpi.edu/gillw3/websys/ph
  p/ex1.php
• Make a PHP script that allows the user to change
  the background color of the

10
Control Structure IF

• IF / ELSE

11
Control Structure Loops
12
Control Structure include

• include(path to file)
• Sources in external text file
• If you specify a file with PHP code, it will be
  executed
• If file is not found, script continues with a
  warning
• require(path to file)
• If file is not found, script fails

13
Control Structure include

• Uses
• Place a common header/footer/navigation file on
  every page in your site
• Reference common code or functions from every
  page in your site
• Require an authorization script (written in PHP)
  on every page you want to secure

14
Functions
15
String Functions
complete list of string functions
http//us3.php.net/manual/en/ref.strings.php
16
Date Functions

• time()
• Returns the current time (on the server)
• Date is represented as Unix Epoch (seconds since
  1/1/1970)
• mktime(hour, minute, second, month, day, year)
• Creates PHP date object

17
Date Functions

• date(format, timestamp)
• Formats date output
• Format rules http//us3.php.net/manual/en/functio
  n.date.php

18
Error Checking

• Turn off error reporting
• error_reporting(0)
• Turn on error reporting
• Error_reporting(E_ALL)

19
In Class Work

• Youve got a website
• You want to check the current time and deliver a
  different look based on the time of day
• Use date() and include() to check the time and
  deliver day.css and night.css to a mock home page.

20
HTML Forms

• New to HTML Forms?
• http//www.w3schools.com/html/html_forms.asp