php对‘[{“id“:“1“,“name“:“cyg”},{“id“:“2“,“name“:“liwen“}]json数据进行修改删除操作

<?php
   $json_string= '[{"id":"1","name":"cyg","age":"27","subject":"海南学校"},{"id":"2","name":"liwen","age":"21","subject":"北京学校"}]';
$data = json_decode($json_string,true);// 把JSON字符串转成PHP数组
//修改操作
/*$data['0']["name"]="aas";//对数组的下标0对象的name属性进行修改操作
$json_strings = json_encode($data);
var_dump($json_strings);*/
//删除操作
/*unset($data['0']["name"]);
$json_strings = json_encode($data);
var_dump($json_strings);*/