预定义常量

下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。

LIBXML_BIGLINES (integer): Allows line numbers greater than 65535 to be reported correctly.
Note:
Only available as of PHP 7.0.0 with Libxml >= 2.9.0
LIBXML_COMPACT (integer): Activate small nodes allocation optimization. This may speed up your application without needing to change the code.
Note:
Only available in Libxml >= 2.6.21
LIBXML_DTDATTR (integer): Default DTD attributes
LIBXML_DTDLOAD (integer): Load the external subset
LIBXML_DTDVALID (integer): Validate with the DTD
LIBXML_HTML_NOIMPLIED (integer): Sets HTML_PARSE_NOIMPLIED flag, which turns off the automatic adding of implied html/body... elements.
Note:
Only available in Libxml >= 2.7.7 (as of PHP >= 5.4.0)
LIBXML_HTML_NODEFDTD (integer): Sets HTML_PARSE_NODEFDTD flag, which prevents a default doctype being added when one is not found.
Note:
Only available in Libxml >= 2.7.8 (as of PHP >= 5.4.0)
LIBXML_NOBLANKS (integer): Remove blank nodes
LIBXML_NOCDATA (integer): Merge CDATA as text nodes
LIBXML_NOEMPTYTAG (integer): Expand empty tags (e.g. <br/> to <br></br>)
Note:
This option is currently just available in the DOMDocument::save and DOMDocument::saveXML functions.
LIBXML_NOENT (integer): Substitute entities
LIBXML_NOERROR (integer): Suppress error reports
LIBXML_NONET (integer): Disable network access when loading documents
LIBXML_NOWARNING (integer): Suppress warning reports
LIBXML_NOXMLDECL (integer): Drop the XML declaration when saving a document
Note:
Only available in Libxml >= 2.6.21
LIBXML_NSCLEAN (integer): Remove redundant namespace declarations
LIBXML_PARSEHUGE (integer): Sets XML_PARSE_HUGE flag, which relaxes any hardcoded limit from the parser. This affects limits like maximum depth of a document or the entity recursion, as well as limits of the size of text nodes.
Note:
Only available in Libxml >= 2.7.0 (as of PHP >= 5.3.2 and PHP >= 5.2.12)
LIBXML_PEDANTIC (integer): Sets XML_PARSE_PEDANTIC flag, which enables pedantic error reporting.
Note:
Available as of PHP >= 5.4.0
LIBXML_XINCLUDE (integer): Implement XInclude substitution
LIBXML_ERR_ERROR (integer): A recoverable error
LIBXML_ERR_FATAL (integer): A fatal error
LIBXML_ERR_NONE (integer): No errors
LIBXML_ERR_WARNING (integer): A simple warning
LIBXML_VERSION (integer): libxml version like 20605 or 20617
LIBXML_DOTTED_VERSION (string): libxml version like 2.6.5 or 2.6.17
LIBXML_SCHEMA_CREATE (integer): Create default/fixed value nodes during XSD schema validation
Note:
Only available in Libxml >= 2.6.14 (as of PHP >= 5.5.2)

User Contributed Notes

vetalstar at mail dot ru 16-Nov-2017 09:26


LIBXML_DOTTED_VERSION option doesn't work.

libxml version: 2.9.4



<?php



echo LIBXML_DOTTED_VERSION;

$xml = new SimpleXMLElement('<fasa_request id="1234567"/>', LIBXML_NOXMLDECL);



?>

@oneseventeen 06-Feb-2011 08:51


When inserting XML DOM Elements inside existing XML DOM Elements that I loaded from an XML file using the following code, none of my new elements were formatted correctly, they just showed up on one line:



<?php 

$dom = DOMDocument::load('file.xml'); 

$dom->formatOutput = true;

//$dom->add some new elements with child nodes somewhere inside the loaded XML using insertBefore();

$dom->saveXML();

//output: everything looks normal but the new nodes are all on one line.

?>



I found I could pass LIBXML_NOBLANKS to the load method and it would reformat the whole document, including my added stuff:

<?php 

$dom = DOMDocument::load('file.xml', LIBXML_NOBLANKS); 

$dom->formatOutput = true;

//$dom->add some new elements with child nodes somewhere inside the loaded XML using insertBefore();

$dom->saveXML();

//output: everything looks newly formatted, including new nodes

?>



Hope this helps, took me hours of trial and error to figure this out!

zachatwork at gmail dot com 10-Feb-2010 08:30


Note: The LIBXML_NOXMLDECL constant is defined in this library but is not supported by DOMDocument (yet).



See also: http://bugs.php.net/bug.php?id=47137



<?php



print "PHP_VERSION:      ".PHP_VERSION."\n";

print "LIBXML_VERSION:   ".LIBXML_VERSION."\n";

print "LIBXML_NOXMLDECL: ".LIBXML_NOXMLDECL."\n";



$dom = new DomDocument();

$dom->loadXML("<foo />");



# This should work but doesn't.



print "DOMDocument doesn't honor LIBXML_NOXMLDECL:\n";

print $dom->saveXML(null,LIBXML_NOXMLDECL);



# This works, and will still work after the above is fixed.



print "Forwards compatible workaround:\n";

$lines = explode("\n", $dom->saveXML(null, LIBXML_NOXMLDECL), 2);

if(!preg_match('/^\<\?xml/', $lines[0]))

    print $lines[0];

print $lines[1];



?>



PHP_VERSION:      5.3.1-0.dotdeb.1

LIBXML_VERSION:   20632

LIBXML_NOXMLDECL: 2

DOMDocument doesn't honor LIBXML_NOXMLDECL:

<?xml version="1.0"?>

<foo/>

Forwards compatible workaround:

<foo/>