PHP如何从对象返回中检索数据

Question

I have a return value and I var_dump() to get the data.

var_dump($values)

this is the result:

object(WP_Error)#171 (2) { ["errors":"WP_Error":private]=> array(1) { ["upload_error"]=> array(1) { [0]=> string(28) "0B1n5jy1RsUExUWNCN01GeXBvWmM" } } ["error_data":"WP_Error":private]=> array(0) { } } 

I am new with PHP Object retrieving I tried foreach but noting happens.

what I am trying to do is to get this value:

["upload_error"]=> array(1) { [0]=> string(28) "0B1n5jy1RsUExUWNCN01GeXBvWmM" }

the 0B1n5jy1RsUExUWNCN01GeXBvWmM that set on upload_error

Answer 1

1. WP_Error is a php class, your values is a instance. see https://codex.wordpress.org/Class_Reference/WP_Error for detail

2. if you want to get error, you can't get it directly because it is private( although you can see it in var_dump), the doc above will tell you how to get it via provided public methods.

3. the following code snippet may give you a better understanding for using foreach on a class instance. you can look at manual for more detail. http://php.net/manual/en/language.oop5.iterations.php

    class WP_Error_Example { private $errors = array(); public $pk = 1; } $e = new WP_Error_Example(); $e2 = new WP_Error_Example(); // #1,#2 in var_dump shows how many instance? var_dump($e); var_dump($e2); // only public value foreach ($e as $k => $v) { var_dump($k, $v); } 

Note: you need to save this to a single file and run it using commandline. eg: php demo.php PS: var_dump it not pretty in commandline.