欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  后端开发

PHP操作json

程序员文章站 2022-05-07 22:35:58
...
json只接受utf-8编码的字符,所以php的函数json_encode()的参数必须是utf-8编码

json格式:

============================

错误的json格式:

$error_json = "{ 'name': 'jack' }"; //json的分隔符只允许使用双引号,不能使用单引号
$error_json = '{ name: "jack" }'; //json键值对的"键"(冒号左边的部分),必须使用双引号
$error_json = '{ "name": "baz", }'; //最后一个值之后不能添加逗号

=============================

正确的json格式

$yes_json= '{"name":"jack"}';

PHP下的操作:

(1).json_encode()函数:将数组和对象,转换为json格式

例如:

①将键/值对数组转为json格式,将变成对象形式的json

  $arr = array ('a'=>1,'b'=>2,'c'=>3,'d'=>4,'e'=>5);
  echo "json化后arr为:".json_encode($arr);
  ==================================================
  json化后arr为:{"a":1,"b":2,"c":3,"d":4,"e":5}

②将索引数组转为json格式,将变成数组形式的json 

  $arr = Array('one', 'two', 'three');
  echo json_encode($arr);
  ==================================================
  ["one","two","three"]

将索引数组强制转化成对象:

  json_encode( (object)$arr );
  或者
  json_encode ( $arr, JSON_FORCE_OBJECT );

③将类的对象转为json格式,只保留public的字段

class ClassA {  
    const ERROR_CODE = '404';  
    public $public_var = 'this is public_var';  
    private $private_var = 'this is private_var';
    protected $protected_var = 'this is protected_var';   
    public function getErrorCode() {  
      return self::ERROR_CODE;  
    }  
 }

========================================

$ClassA = new ClassA;  
$classA_json = json_encode($ClassA);  
echo $classA_json;
========================================
{"public_var":"this is public_var"}

(2).json_decode()函数,将json格式的字符串转化为php变量,默认转为object对象,当传入第二个参数为true时,转为php数组

例如:

①.转为php对象  

$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}
var_dump($json);
=============================================
object(stdClass)#1 (5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}

②.转为php数组

$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';
var_dump(json_decode($json, true));
=============================================
array(5) {
["a"] => int(1)
["b"] => int(2)
["c"] => int(3)
["d"] => int(4)
["e"] => int(5)
}

以上就介绍了PHP操作json,包括了方面的内容,希望对PHP教程有兴趣的朋友有所帮助。