diff options
Diffstat (limited to 'php.html.markdown')
| -rw-r--r-- | php.html.markdown | 47 |
1 files changed, 39 insertions, 8 deletions
diff --git a/php.html.markdown b/php.html.markdown index ce228870..e1bb86a0 100644 --- a/php.html.markdown +++ b/php.html.markdown @@ -11,7 +11,7 @@ This document describes PHP 5+. ```php <?php // PHP code must be enclosed with <?php tags -// If your php file only contains PHP code, it is best practise +// If your php file only contains PHP code, it is best practice // to omit the php closing tag. // Two forward slashes start a one-line comment. @@ -59,6 +59,9 @@ $float = 1.234; $float = 1.2e3; $float = 7E-10; +// Delete variable +unset($int1) + // Arithmetic $sum = 1 + 1; // 2 $difference = 2 - 1; // 1 @@ -69,7 +72,7 @@ $quotient = 2 / 1; // 2 $number = 0; $number += 1; // Increment $number by 1 echo $number++; // Prints 1 (increments after evaluation) -echo ++$number; // Prints 3 (increments before evalutation) +echo ++$number; // Prints 3 (increments before evaluation) $number /= $float; // Divide and assign the quotient to $number // Strings should be enclosed in single quotes; @@ -104,7 +107,7 @@ echo 'This string ' . 'is concatenated'; /******************************** * Constants */ - + // A constant is defined by using define() // and can never be changed during runtime! @@ -136,6 +139,11 @@ echo $associative['One']; // prints 1 $array = ['One', 'Two', 'Three']; echo $array[0]; // => "One" +// Add an element to the end of an array +$array[] = 'Four'; + +// Remove element from array +unset($array[3]); /******************************** * Output @@ -176,6 +184,11 @@ $y = 0; echo $x; // => 2 echo $z; // => 0 +// Dumps type and value of variable to stdout +var_dump($z); // prints int(0) + +// Prints variable to stdout in human-readable format +print_r($array); // prints: Array ( [0] => One [1] => Two [2] => Three ) /******************************** * Logic @@ -199,7 +212,7 @@ assert($c >= $d); // The following will only be true if the values match and are the same type. assert($c === $d); assert($a !== $d); -assert(1 == '1'); +assert(1 === '1'); assert(1 !== '1'); // Variables can be converted between types, depending on their usage. @@ -440,6 +453,13 @@ class MyClass static $staticVar = 'static'; + // Static variables and their visibility + public static $publicStaticVar = 'publicStatic'; + // Accessible within the class only + private static $privateStaticVar = 'privateStatic'; + // Accessible from the class and subclasses + protected static $protectedStaticVar = 'protectedStatic'; + // Properties must declare their visibility public $property = 'public'; public $instanceProp; @@ -458,10 +478,17 @@ class MyClass print 'MyClass'; } + //final keyword would make a function unoverridable final function youCannotOverrideMe() { } +/* + * Declaring class properties or methods as static makes them accessible without + * needing an instantiation of the class. A property declared as static can not + * be accessed with an instantiated class object (though a static method can). +*/ + public static function myStaticMethod() { print 'I am static'; @@ -650,10 +677,14 @@ $cls = new SomeOtherNamespace\MyClass(); ## More Information -Visit the [official PHP documentation](http://www.php.net/manual/) for reference and community input. +Visit the [official PHP documentation](http://www.php.net/manual/) for reference +and community input. -If you're interested in up-to-date best practices, visit [PHP The Right Way](http://www.phptherightway.com/). +If you're interested in up-to-date best practices, visit +[PHP The Right Way](http://www.phptherightway.com/). -If you're coming from a language with good package management, check out [Composer](http://getcomposer.org/). +If you're coming from a language with good package management, check out +[Composer](http://getcomposer.org/). -For common standards, visit the PHP Framework Interoperability Group's [PSR standards](https://github.com/php-fig/fig-standards). +For common standards, visit the PHP Framework Interoperability Group's +[PSR standards](https://github.com/php-fig/fig-standards). |