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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.
#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);
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. 076402276aae5dbec7f672f8f4e5cc81 to 0c6dc11e160d3b678d68754cc175188a0b9f73f8e206867bd1f5dc5957dbcb38), 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't forget me this weekend!</body> </note>
Example 1
Create a SimpleXMLElement object from the URL:
<?php $xml=new SimpleXMLElement("note.xml",NULL,TRUE); echo $xml->asXML(); ?>
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't forget me this weekend!</body> </note> XML; $xml=new SimpleXMLElement($note); echo $xml->body; ?>
Output:
Don't forget me this weekend!
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