PHP: Difference between revisions

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       parent::__construct();
       parent::__construct();
* trait: a trait is similar to a class, but only intended to group functionality in a fine-grained and consistent way. It is not possible to instantiate a Trait on its own. It is an addition to traditional inheritance and enables horizontal composition of behavior; that is, the application of class members without requiring inheritance.
* trait: a trait is similar to a class, but only intended to group functionality in a fine-grained and consistent way. It is not possible to instantiate a Trait on its own. It is an addition to traditional inheritance and enables horizontal composition of behavior; that is, the application of class members without requiring inheritance.
==PDO==
PHP Data Objects ('''PDO''') is a Database Access Abstraction Layer.


==Exceptions==
==Exceptions==

Revision as of 09:14, 3 September 2018

Comments

// single line
/*
   multiple line
*/

Functions

  • function arguments:
    • bool
    • int
    • float
    • string
    • array
    • callable
    • self
    • iterable
    • object
    • class
    • interface

OO

  • namespace?
  • interface?
  • self?
  • method
  • $this?
  • use?
  • annotations?
  • visibility:
    • private: only in this class
    • protected: only in derived classes
    • public: everywhere
  • ctor
function __construct() {
  parent::__construct(); // has to be called explicitly
  ...
}

There can only be one ctor which can have function parameters.

  • dtor
function __destruct() {
  parent::__destruct(); // has to be called explicitly
}
  • inheritance
class B extends A
{
   public function __construct()
   {
     parent::__construct();
  • trait: a trait is similar to a class, but only intended to group functionality in a fine-grained and consistent way. It is not possible to instantiate a Trait on its own. It is an addition to traditional inheritance and enables horizontal composition of behavior; that is, the application of class members without requiring inheritance.

PDO

PHP Data Objects (PDO) is a Database Access Abstraction Layer.

Exceptions

The base Exception class provided in PHP 5 can be extended.

Resources