Getting Started

class Student { public function \_\_construct($name) { $this->name = $name; } } $alex = new Student("Alex"); 

See: Classes

const MY\_CONST = "hello"; echo MY_CONST; # => hello # => MY\_CONST is: hello echo 'MY\_CONST is: ' . MY_CONST; 

# This is a one line shell-style comment // This is a one line c++ style comment /\* This is a multi line comment yet another line of comment \*/ 

function add($num1, $num2 = 1) { return $num1 + $num2; } echo add(10); # => 11 echo add(10, 5); # => 15 

See: Functions

#vars.php

<?php // begin with a PHP open tag. $fruit = 'apple'; echo "I was imported"; return 'Anything you like.'; ?> 

#test.php

<?php include 'vars.php'; echo $fruit . "\n"; # => apple /\* Same as include, cause an error if cannot be included\*/ require 'vars.php'; // Also works include('vars.php'); require('vars.php'); // Include through HTTP include 'http://x.com/file.php'; // Include and the return statement $result = include 'vars.php'; echo $result; # => Anything you like. ?> 

$x = 1; $y = 2; $sum = $x + $y; echo $sum; # => 3 

See: Operators

$num = [1, 3, 5, 7, 9]; $num[5] = 11; unset($num[2]); // Delete variable print\_r($num); # => 1 3 7 9 11 echo count($num); # => 5 

See: Arrays

$url = "quickref.me"; echo "I'm learning PHP at $url"; // Concatenate strings echo "I'm learning PHP at " . $url; $hello = "Hello, "; $hello .= "World!"; echo $hello; # => Hello, World! 

See: Strings

$boolean1 = true; $boolean2 = True; $int = 12; $float = 3.1415926; unset($float); // Delete variable $str1 = "How are you?"; $str2 = 'Fine, thanks'; 

See: Types

<?php // begin with a PHP open tag. echo "Hello World\n"; print("Hello quickref.me"); ?> 

PHP run command

$ php hello.php