This article mainly introduces the method of PHP using new StdClass() to create empty objects. It analyzes the creation and use of PHP empty objects based on specific examples. Friends in need can refer to the examples in this article.
Describes how PHP uses new StdClass() to create an empty object. Share it with everyone for your reference, the details are as follows:
PHP can use $object = new StdClass();
to create an empty object without member methods and properties.
Many times, programmers will put some information such as parameter configuration items in arrays for use, but array operations are not very convenient. Many times, object operators->xxx are used instead of array operations. The symbol ['xxx'] is much more convenient. So you need to create an empty object to store the required attribute names and attribute values into the object.
However, there is no syntax like var object = {};
in Javascript in PHP.
PHP can use at least 3 methods to create an empty object
Method 1: Write an empty class
It can barely complete the task, but there is nothing special pattern.
<?php class cfg { } $cfg = new cfg; $cfg->dbhost = 'www.jb51.net'; echo $cfg->dbhost; ?>
Method 2: Instantiate the StdClass class
The StdClass class is a base class in PHP. However, what is strange is that it is almost never mentioned in the PHP manual. This class, at least in the PHP index, cannot be searched.
The StdClass class does not have any member methods or member attributes. After instantiation, it is an empty object.
<?php $cfg = new StdClass(); $cfg->dbhost = 'www.jb51.net'; echo $cfg->dbhost; ?>
Method 3: Tossing json_encode() and json_decode()
This method is to pass an empty JSON object through json_decode()
Convert to PHP's StdClass empty object.
Similarly, you can convert an array into JSON through json_encode()
, and then convert JSON into a StdClass object through json_decode()
,
For these two functions, please refer to the PHP manual.
<?php $cfg = json_decode('{}'); $cfg->dbhost = 'www.jb51.net'; echo $cfg->dbhost; ?>
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