How to use php __construct function-PHP Problem-php.cn

Home

Backend Development

PHP Problem

How to use php __construct function

藏色散人

May 27, 2019 pm 01:24 PM

php __construct function is used to create a new SimpleXMLElement object. The syntax is __construct(data, options, data_is_url, ns, is_prefix). The parameter data is required.

How to use php __construct function

#php How to use the __construct function?

Definition and Usage

__construct() function creates a new SimpleXMLElement object.

Syntax

__construct(data,options,data_is_url,ns,is_prefix);

Copy after login

Parameters

data Required. A well-formed XML string or the path or URL of an XML document (if data_is_url is TRUE).

options Optional. Specifies additional Libxml parameters. Set by specifying the option to 1 or 0 (TRUE or FALSE, such as LIBXML_NOBLANKS(1)).

Possible values:

● LIBXML_COMPACT - Activates an optimized configuration of the node (can speed up the application)

● LIBXML_DTDATTR - Sets the default DTD attribute

● LIBXML_DTDLOAD - Load additional subset

● LIBXML_DTDVALID - Verify DTD validity

● LIBXML_NOBLANKS - Remove empty nodes

● LIBXML_NOCDATA - Set CDATA to text node

● LIBXML_NOEMPTYTAG - expands empty tags (e.g.
to

), only valid in DOMDocument->save() and DOMDocument->saveXML() functions

● LIBXML_NOENT - Alternative entity

● LIBXML_NOERROR - Do not display error reports

● LIBXML_NONET - Stop access to the network while loading the document

● LIBXML_NOWARNING - Do not display Warning Report

● LIBXML_NOXMLDECL - Discard XML declarations when storing a document

● LIBXML_NSCLEAN - Remove redundant namespace declarations

● LIBXML_PARSEHUGE - Set the XML_PARSE_HUGE flag for relaxation Any restrictions imposed by the parser. This will affect things like the maximum document depth and text node size limits.

● LIBXML_XINCLUDE - Use XInclude instead

● LIBXML_ERR_ERROR - Get correctable errors

● LIBXML_ERR_FATAL - Get fatal errors

● LIBXML_ERR_NONE - Get no errors

● LIBXML_ERR_WARNING - Get a simple warning

● LIBXML_VERSION - Get the libxml version (e.g. 20605 or 20617)

● LIBXML_DOTTED_VERSION - Get the dotted libxml version (e.g. 2.6.5 or 2.6.17)

data_is_url Optional. If TRUE indicates that data is the path or URL of the XML document rather than string data. Default is FALSE.

ns Optional. Specifies a namespace prefix or URI.

is_prefix Optional. Specifies a boolean value. TRUE if ns is a prefix, FALSE if ns is a URI. Default is FALSE.

Return value:

Returns the SimpleXMLElement object representing data.

PHP Version: 5.0.1

PHP Change Log:

PHP 5.1.2: Added options and data_is_url parameters.

PHP 5.2: Added ns and is_prefix parameters.

Example

Suppose we have the following XML file, "note.xml":

<?xml version="1.0" encoding="ISO-8859-1"?>
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don&#39;t forget me this weekend!</body>
</note>

Copy after login

Example 1

Create a SimpleXMLElement object from the URL:

<?php
$xml=new SimpleXMLElement("note.xml",NULL,TRUE);
echo $xml->asXML();
?>

Copy after login

Instance 2

The function creates a new SimpleXMLElement object and then outputs the content of the body node :

<?php
$note=<<<XML
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don&#39;t forget me this weekend!</body>
</note>
XML;
$xml=new SimpleXMLElement($note);
echo $xml->body;
?>

Copy after login

Output:

Don&#39;t forget me this weekend!

Copy after login

The above is the detailed content of How to use php __construct function. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn