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The underscore before the Php constructor construct is a double underscore
- 怪我咯Original
- 2017-07-06 09:55:382160browse
When I write PHP classes recently, I always encounter the error of function non object. I know that the class is not instantiated, but I just don’t know where the error is.
Definition and usage
construct() function creates a new SimpleXMLElement object.
If successful, the function returns an object. On failure, returns false.
Syntax
construct(data,options,is_url,ns,is_prefix)
| Parameters | Description |
|---|---|
| data | Required. A well-formed XML string or the path or URL of an XML document. |
| options | Optional. Specifies additional Libxml parameters. |
| is_url | Optional. Specifies whether the data parameter is a URL. The default is false. |
| ns | Optional. |
| is_prefix | Optional. |
Return value
Returns a SimpleXMLElement object representing the data.
Example
<?php $xmlstring = <<<XML <?xml version="1.0" encoding="ISO-8859-1"?> <note> <to>George</to> <from>John</from> <heading>Reminder</heading> <body>Don't forget the meeting!</body> </note> XML; $xml = new SimpleXMLElement($xmlstring); echo $xml->body[0]; ?>
Output similar to:
Don't forget the meeting!
后来看construct的前_是一个，我靠，上次也是这个错误，忘了，现在记着了
function construct()
{}
不是
function _construct()
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