Summary of new features of PHP53

This paper summarizes and analyzes the new characteristics of PHP5.3. Share to everyone for your reference, as follows:

1. namespace resolves the problem of class, function and constant name conflicts

2. When a static binding inherits, the parent class can call the subclass directly to override the parent class's method

Class A {public  static function who () {    echo __class__;  }  public static function test () {    static::who ();//Late static binding starts here  }}class B extends A {public  static function () {    echo __class__;  }} B::test ();

3, anonymous function, also called the closure function (closures), allows temporary creation of a function without a specified name. Most often used as a callback function

The anonymous function does the callback function Uasort ($arr, function ($a, $b) {})

The closure function can also be used as the value of a variable

$FN = function ($a) {  echo $a;}; $FN (1);

PHP automatically converts an expression into an object instance of the built-in class closure

$FN = function ($a) {  echo $a;}; EE ($FN);/** * Closure Object (  [parameter] = Array    (      [$a] =     )) */

Anonymous functions are now implemented through the closure class. is not yet stable and does not apply to formal development

3,?: operator

$a = 0; $b = 2;ee ($a?: $b); # 2 similar to JS | |

4, new constant __dir_

5, new garbage collection mechanism, solve the problem of circular reference

Gc_enable (); Activates the Loop reference collector, which turns on Var_dump (Gc_collect_cycles ()) by default; Forced reclamation of an invalid variable gc_disable (); Disable GC

Read more about PHP related content readers can view the topic: "PHP Basic Grammar Introductory Tutorial", "PHP error and Exception handling method summary" and "PHP common functions and Skills summary"

I hope this article is helpful to you in PHP programming.

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