.Open PHP Samples
This page was created by Paul Conrad as part of his Graduate
Independent Study (CSCI695) of the syntax and semantics of the PHP
language.

This page contains all of the code samples for PHP.

. See Also

For a quick, concise reference to terms used through out this page, see 
.See ./php.glossary.html
which contains meta-linguistic terms, lexemes, and keyword definitions based on
the C++ glossary found at
.See http://www.csci.csusb.edu/dick/samples/c++.glossary.html
with the appropriate adaptations to PHP.

. PHP comments
 
.As_is <?php
.As_is      /* Initialize some variables using C style comments
.As_is 	       $a - contains a-coefficient
.As_is 	       $b - contains b-coefficient
.As_is 	       $x - value we are evaluating
.As_is 	       $y - result from evaluating equation */
.As_is      $a = 1; $b = 2; $x = 1;
.As_is      $y = $a * $x + $b;
.As_is      if ( $y < 5 )                // C++ style comment, check if y<5
.As_is      {
.As_is              # Shell style comment, display something when y<5
.As_is              echo "Guess what?  y is less than 5!";
.As_is      }
.As_is ?>

To see this script in action, visit 
.See ./php_samples/comment_sample.php
.
  
. PHP variables

.As_is <?php
.As_is      $count = 0;     // Set count equal to 0
.As_is      $_xval = 5;
.As_is      $_yval = 1.0;
.As_is      $some_string = "Hello There!";
.As_is      $will i work=6; // This does not work!!!
.As_is      $3blindmice=3;  // Same here, does not work
.As_is ?>

To see this script in action, visit 
.See ./php_samples/variable_sample.php
(script does not include the two lines that will fail).

. PHP functions

.As_is <?php
.As_is      function m_x_plus_b($m, $x, $b) {
.As_is            return $m*$x+$b;
.As_is      }
.As_is      $slope=1.5;
.As_is      $x=2;
.As_is      $b=3;
.As_is      echo "y = ".m_x_plus_b($slope,$x,$b)."<br>";
.As_is ?>

To see this script in action, visit 
.See ./php_samples/function_sample1.php
.

The following script is an example of case-insensitivity with
function names in PHP.  To see this script in action, visit 
.See ./php_samples/function_sample2.php
.
 
.As_is <?php
.As_is      // This is a sample script from Paul Conrad's Independent Study
.As_is      // This script will call the function named foo showing case insensitivity.
.As_is      function foo($my_string) {
.As_is              echo "$"."my_string = $my_string<br>";
.As_is      }
.As_is      foo("foo is foo");
.As_is      Foo("Foo is foo");
.As_is      FoO("FoO is foo");
.As_is      FOO("FOO is foo");
.As_is ?>


The two following sample scripts show two different ways of using the same anonymous function.

.As_is <?php
.As_is        $lambda=create_function('$a,$b','return(strlen($a)-strlen($b));');
.As_is        $array=array('really long string here, boy','middling length','larger');
.As_is        usort($array,$lambda);
.As_is        print_r($array);
.As_is ?>

To see this script in action, visit 
.See ./php_samples/anonymous_function.php
.

.As_is <?php
.As_is        $array=array('really long string here, boy','middling length','larger');
.As_is        usort($array,create_function('$a,$b','return(strlen($a)-strlen($b));'));
.As_is        print_r($array);
.As_is ?>

To see this script in action, visit 
.See ./php_samples/anonymous_function2.php

. PHP Arrays
Arrays are associative and can use strings(in quotes) or integers.

.Hole PHP_Arrays

. Getting data from an HTML form
Data sent from an HTML form is presented to a PHP script as an array.
It may be the array $_GET or the array of $_POST.  

Before you access
an element in one of these arrays you need to check to see it exists.
Recall that any PHP script can be called by typing inits URL... and so
any or no data can be delivered.  The following function handles this.
.As_is function get($key)
.As_is {
.As_is 	if (array_key_exists($key,$_POST))
.As_is 		return $_POST[$key];
.As_is 	else
.As_is 		 return "";
.As_is }
.As_is $SUBJECT=get('subject');
.As_is $FROM=get('from');
.As_is $MESSAGE=get('message');
.As_is $SIGNED=get('signed');

. PHP classes

.As_is <?php
.As_is      class Programmer {
.As_is           // Class Properties
.As_is           var $name;         // Programmer's name
.As_is           var $experience;   // How long has been programming
.As_is           var $lang;         // Favorite Language
.As_is           var $education;    // Highest degree earned
.As_is           // Class Constructor - function same name as the class
.As_is           function Programmer($name, $experience, $lang, $education) {
.As_is                $this->name=$name;
.As_is                $this->experience=$experience;
.As_is                $this->lang=$lang;
.As_is                $this->education=$education;
.As_is           }
.As_is           // Getter/Setter functions for all properties in the class
.As_is           function get_name() {
.As_is                return $this->name;
.As_is           }
.As_is           function set_name($newname) {
.As_is                $this->name = $newname;
.As_is           }
.As_is           function get_experience() {
.As_is                return $this->experience;
.As_is           }
.As_is           function set_experience($newexperience) {
.As_is                $this->experience = $newexperience;
.As_is           }
.As_is           function get_lang() {
.As_is                return $this->lang;
.As_is           }
.As_is           function set_lang($newlang) {
.As_is                $this->lang = $newlang;
.As_is           }
.As_is           function get_education() {
.As_is                return $this->education;
.As_is           }
.As_is           function set_education($neweducation) {
.As_is                $this->education = $neweducation;
.As_is           }
.As_is           // Utility data dump function
.As_is           function output() {
.As_is                echo "Programmer Name: ".$this->name."<br>";
.As_is                echo $this->name." has ".$this->experience." years of programming experience.<br>";
.As_is                echo $this->lang." is ".$this->name."'s favorite programming language.<br>";
.As_is                echo $this->name." holds the degree: ".$this->education."<br><br>";
.As_is           }
.As_is      }
.As_is      // Instantiating a programmer
.As_is      $paul = new Programmer('Paul Conrad',12,'C++','Bachelor of Science in Computer Science');
.As_is      $paul->output();
.As_is      // Oops, Paul has programmed alot longer than 12 year, really is 22 years
.As_is      $paul->set_experience(22);
.As_is      $paul->output();
.As_is ?>

To see this script in action, visit
.See ./php_samples/class_sample.php
.

. PHP constants

.As_is <?php
.As_is      define('school',"California State University at San Bernardino");
.As_is      define('programs',4);
.As_is      echo "Our school is ".school."<br>";
.As_is      echo "Our school's Computer Science Dept has ".programs." academic programs";
.As_is ?>

To see this script in action, visit 
.See ./php_samples/constant_sample.php
.

. PHP Sample Code Quick Reference

.Table Example PHP Script	Source File	Description
.Row
.See ./php_samples/anonymous_function.php
.Item 
.See ./php_samples/anonymous_function.txt
.Item Sample of anonymous functions at work.
.Row
.See ./php_samples/anonymous_function2.php 
.Item
.See ./php_samples/anonymous_function2.txt
.Item Another anonymous function sample, no assigned variable, though (YAGNI).
.Row
.See ./php_samples/assignment1.php
.Item
.See ./php_samples/assignment1.txt
.Item Sample of assigning values to variables and doing some strange operations.
.Row
.See ./php_samples/block.php
.Item 
.See ./php_samples/block.txt
.Item Example of block scope and } is not required when ?> tag encountered.
.Row
.See ./php_samples/class_extends.php
.Item
.See ./php_samples/class_extends.txt
.Item Sample showing how classes are inherited in PHP.
.Row
.See ./php_samples/class_sample.php
.Item
.See ./php_samples/class_sample.txt
.Item Sample class of a class named Programmer.
.Row
.See ./php_samples/comment_sample.php
.Item
.See ./php_samples/comment_sample.txt
.Item Sample showing how comments can be done in PHP.
.Row
.See ./php_samples/constant_sample.php
.Item
.See ./php_samples/constant_sample.txt
.Item Sample showing how to define constants in PHP.
.Row
.See ./php_samples/const_in_class.php
.Item
.See ./php_samples/const_in_class.txt
.Item Experiment to see what the scope of define'd constants are in PHP.
.Row
.See ./php_samples/define1.php
.Item
.See ./php_samples/define1.txt
.Item A way to define a constant in PHP.  Just displays a 1 - constant is defined.
.Row
.See ./php_samples/define2.php
.Item
.See ./php_samples/define2.txt
.Item Another way to define a constant in PHP.  Displays the value of the constant.
.Row
.See ./php_samples/define3.php
.Item
.See ./php_samples/define3.txt
.Item An experiment in which 'a' contains the constant, and $b is 1.
.Close.Table

.Close PHP Samples