泽民博客 ☰ Menu

JsonSerializable

PHP 中 json_encode() 只将索引数组（indexed array）转为数组格式，而将关联数组（associative array）转为对象格式。



$arr = array(
‘0’=>’a’,’1’=>’b’,’2’=>’c’,’3’=>’d’
);
echo json_encode($arr);
结果是：



[“a”,”b”,”c”,”d”]
而不是



{“0”:”a”,”1”:”b”,”2”:”c”,”3”:”d”}
强制转成对象



$arr = array(
‘0’=>’a’,’1’=>’b’,’2’=>’c’,’3’=>’d’
);
echo json_encode((object)$arr);
输出结果：



{“0”:”a”,”1”:”b”,”2”:”c”,”3”:”d”}



json_encode()序列化一个对象时，会先提取(get_object_vars)对象的公有(public、static)属性合并为一个数组，再进行序列化。private、protected属性以及类方法都将被丢弃。



但是如果继承自arrayObject 所有属性会被丢弃，除非继承JsonSerializable 并且实现jsonSerialize方法





<?php
/**



  • Created by PhpStorm.

  • Date: 20/10/24

  • Time: 21:34

  • @category Category

  • @package FileDirFileName

  • @link ${link}
    */
    class A{
    public $a;
    public $_b;
    private $c;
    static $d;
    protected $e;
    public function __construct($a, $b){
    $this->a = $a;
    $this->_b = $b;
    $this->c=4;
    $this->d=5;
    $this->e=6;
    }
    public function sum(){
    return $this->a + $this->b;
    }
    }
    $obj = new A(1,2);
    echo json_encode($obj);



class B extends \ArrayObject {
public $a;
public $_b;
private $c;
static $d;
protected $e;
public function __construct($a, $b){
$this->a = $a;
$this->_b = $b;
$this->c=4;
$this->d=5;
$this->e=6;
}
public function sum(){
return $this->a + $this->b;
}
public function jsonSerialize(){
$aRet=[];
$aRet[‘f’]=7;
return $aRet;
}
}
$obj = new B(1,2);
echo json_encode($obj);



class C extends \ArrayObject implements JsonSerializable {
public $a;
public $_b;
private $c;
static $d;
protected $e;
public function __construct($a, $b){
$this->a = $a;
$this->_b = $b;
$this->c=4;
$this->d=5;
$this->e=6;
}
public function sum(){
return $this->a + $this->b;
}



public function jsonSerialize()

{

    parent::serialize(); // TODO: Change the autogenerated stub

    $aRet=[];

    foreach ($this as $k=>$v){

        $aRet[$k]=$v;//走不进去

    }



    $this['g']=8; //仅仅可以输出这个

    $aRet=$this->getArrayCopy();

    $aRet['f']=7;

    return $aRet;

} } $obj = new C(1,2); echo json_encode($obj); //$ php json.php //{"a":1,"_b":2,"d":5}{}{"g":8,"f":7}


https://segmentfault.com/a/1190000021314708
https://blog.csdn.net/fdipzone/article/details/79771348



Category php