php如何把获取到的json信息转成数组

{"secret":"c43bb290aab8d7969710472634d4ab98","last_login_time":"2017-04-11 12:05:26","errcode":200,"errmsg":"success","content":{"code":"201702211139481","actual_name":"\u6c9b\u83e1","idcard":"44088219899201925","sex":"\u7537","company_name":"\u9ad8\u65b0\u6280\u672f\u4ea7\u4e1a\u56ed\u7b2c30\u5206\u90e8","company_id":"111","imgurl":null,"last_login_ip":"::1"}}

如何把上一段信息转成数组。

用json_decode解析字符串

 <?php 
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}'; 
var_dump(json_decode($json)); 
var_dump(json_decode($json, true)); 
?> 

json_decode($json, true)