How to handle Warning: SimpleXMLElement :: __ construct ()?

Question

I get this error when I start the local host if the Internet is disconnected (if the Internet is connected to it normally) I want to handle this error, "the error may show", but you want to handle a non-fatal error in PHP p.

Warning: SimpleXMLElement::__construct() [simplexmlelement.--construct]: php_network_getaddresses: getaddrinfo failed: No such host is known. in F:\xampp\htdocs\shoptpoint\sections\docType_head_index.php on line 30 

but I am trying to handle using try-catch. Below is my code

 $apiurl="http://publisher.usb.api.shopping.com/publisher/3.0/rest/GeneralSearch?apiKey=78b0db8a-0ee1-4939-a2f9-d3cd95ec0fcc&trackingId=7000610&categoryId='5855855'"; try{ new SimpleXMLElement($apiurl,null, true); }catch(Exception $e){ echo $e->getMessage(); } 

How to handle the error and my page can complete the project?

Answer 1

Using set_error_handler, you can do the following to convert any notifications / warnings caused by SimpleXMLElement into a catching Exception.

Do the following: -

 <?php function getData() { return new SimpleXMLElement('http://10.0.1.1', null, true); } $xml = getData(); /* PHP Warning: SimpleXMLElement::__construct(http://10.0.1.1): failed to open stream: Operation timed out PHP Warning: SimpleXMLElement::__construct(): I/O warning : failed to load external entity "http://10.0.1.1" PHP Fatal error: Uncaught exception 'Exception' with message 'String could not be parsed as XML' */ 

See how we get 2 warnings before throwing an exception from SimpleXMLElement? Well, we can convert them to Exception as follows: -

 <?php function getData() { set_error_handler(function($errno, $errstr, $errfile, $errline) { throw new Exception($errstr, $errno); }); try { $xml = new SimpleXMLElement('http://10.0.1.1', null, true); }catch(Exception $e) { restore_error_handler(); throw $e; } return $xml; } $xml = getData(); /* PHP Fatal error: Uncaught exception 'Exception' with message 'SimpleXMLElement::__construct(http://10.0.1.1): failed to open stream: Operation timed out' */ 

Good luck

Anthony.

Answer 2

If for some reason you do not want to install an error handler, you can also use some libxml functions to suppress E_WARNING from raising:

 // remembers the old setting and enables usage of libxml internal error handler $previousSetting = libxml_use_internal_errors(true); // still need to try/catch because invalid XML raises an Exception try { // XML is missing root node new SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?>',null, true); } catch(Exception $e) { echo $e->getMessage(); // this won't help much: String could not be parsed as XML $xmlError = libxml_get_last_error(); // returns object of class LibXMLError or FALSE if ($xmlError) { echo $xmlError->message; // this is more helpful: Start tag expected, '<' not found } } // sets libxml usage of internal error handler to previous setting libxml_use_internal_errors($previousSetting); 

Alternatively, you can use libxml_get_errors() instead of libxml_get_last_error() to get all errors. With it, you can get all the errors associated with LibXMLError XML as an array of LibXMLError objects.

Some useful links:

• https://www.php.net/manual/en/function.libxml-use-internal-errors.php
• https://www.php.net/manual/en/function.libxml-get-last-error.php