ArrayAccess (interface)

介绍

(PHP 5 >= 5.0.0, PHP 7)

提供数组访问对象的接口。

界面简介

ArrayAccess {

/* Methods */

abstract public boolean offsetExists ( mixed $offset )

abstract public mixed offsetGet ( mixed $offset )

abstract public void offsetSet ( mixed $offset , mixed $value )

abstract public void offsetUnset ( mixed $offset )

}

示例＃1基本用法

<?php
class?obj?implements?ArrayAccess?{
????private?$container?=?array();

????public?function?__construct()?{
????????$this->container?=?array(
????????????"one"???=>?1,
????????????"two"???=>?2,
????????????"three"?=>?3,
????????);
????}

????public?function?offsetSet($offset,?$value)?{
????????if?(is_null($offset))?{
????????????$this->container[]?=?$value;
????????}?else?{
????????????$this->container[$offset]?=?$value;
????????}
????}

????public?function?offsetExists($offset)?{
????????return?isset($this->container[$offset]);
????}

????public?function?offsetUnset($offset)?{
????????unset($this->container[$offset]);
????}

????public?function?offsetGet($offset)?{
????????return?isset($this->container[$offset])???$this->container[$offset]?:?null;
????}
}

$obj?=?new?obj;

var_dump(isset($obj["two"]));
var_dump($obj["two"]);
unset($obj["two"]);
var_dump(isset($obj["two"]));
$obj["two"]?=?"A?value";
var_dump($obj["two"]);
$obj[]?=?'Append?1';
$obj[]?=?'Append?2';
$obj[]?=?'Append?3';
print_r($obj);
?>

上面的例子会输出类似于：

bool(true)
int(2)
bool(false)
string(7) "A value"
obj Object
(
    [container:obj:private] => Array
        (
            [one] => 1
            [three] => 3
            [two] => A value
            [0] => Append 1
            [1] => Append 2
            [2] => Append 3
        )

)

介绍

界面简介

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