libxml
PHP Manual

Predefined Constants

The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.

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_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 namespaces declarations
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
PHP Manual