This keyword usage analysis _php techniques in PHP

This example describes the use of this keyword in PHP. Share to everyone for your reference, specific as follows:

The following defines a cart class

<?php
class Cart
{
  var $items;//items in the cart//
  put $num $artnr into the car
  function Add_item ($ARTNR, $num) c6/>{
    $this->items[$artnr] + = $num;
  }
  Take $num $artnr out of the car
  function Remove_item ($ARTNR, $num)
  {
    if ($this->items[$artnr] > $num) {
    $this->items[$artnr]-= $num;
      return true;
    } else {return false;}}}
? >

With a piece of code that explains the problem, within the definition of a class, you can't know what name the object is accessible to: when you write the Cart class, the name of the object will be named $cart or $another _cart. Therefore you cannot use $cart->items in the class. However, in order to access its own functions and variables within the class definition, the pseudo variable $this can be used to achieve this goal. $this variable can be understood as "my own" or "current object." Thus the ' $this->>items[$artnr] + + $num ' can be understood as ' $artnr counter plus $num ' of the array of my own objects plus $artnr ' or ' $num counter of the objects array of the current object.

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I hope this article will help you with the PHP program design.