XXIV. DOM XML functions
Introduction
| Warning |
This extension is EXPERIMENTAL. The behaviour of this extension -- including the names of its functions and anything else documented about this extension -- may change without notice in a future release of PHP. Use this extension at your own risk. |
The DOM XML extension has been overhauled in PHP 4.3.0 to better comply with the DOM standard. The extension still contains many old functions, but they should no longer be used. In particular, functions that are not object-oriented should be avoided.
The extension allows you to operate on an XML document with the DOM API. It also provides a function domxml_xmltree() to turn the complete XML document into a tree of PHP objects. Currently, this tree should be considered read-only — you can modify it, but this would not make any sense since DomDocument_dump_mem() cannot be applied to it. Therefore, if you want to read an XML file and write a modified version, use DomDocument_create_element(), DomDocument_create_text_node(), set_attribute(), etc. and finally the DomDocument_dump_mem() function.
Requirements
This extension makes use of the GNOME XML library. Download and install this library. You will need at least libxml-2.4.14. To use DOM XSLT features you can use the libxslt library and EXSLT enhancements from http://www.exslt.org/. Download and install these libraries if you plan to use (enhanced) XSLT features. You will need at least libxslt-1.0.18.
Installation
This extension is only available if PHP was configured with --with-dom[=DIR]. Add --with-dom-xslt[=DIR] to include DOM XSLT support. DIR is the libxslt install directory. Add --with-dom-exslt[=DIR] to include DOM EXSLT support, where DIR is the libexslt install directory.
Note to Win32 Users: In order to enable this module on a Windows environment, you must copy one additional file from the DLL folder of the PHP/Win32 binary package to the SYSTEM32 folder of your Windows machine (Ex: C:\WINNT\SYSTEM32 or C:\WINDOWS\SYSTEM32). For PHP <= 4.2.0 copy libxml2.dll, for PHP >= 4.3.0 copy iconv.dll from the DLL folder to your SYSTEM32 folder.
Deprecated functions
There are quite a few functions that do not fit into the DOM standard and should no longer be used. These functions are listed in the following table. The function DomNode_append_child() has changed its behaviour. It now adds a child and not a sibling. If this breaks your application, use the non-DOM function DomNode_append_sibling().
Table 1. Deprecated functions and their replacements
| Old function | New function |
|---|---|
| xmldoc | domxml_open_mem() |
| xmldocfile | domxml_open_file() |
| domxml_new_xmldoc | domxml_new_doc() |
| domxml_dump_mem | DomDocument_dump_mem() |
| domxml_dump_mem_file | DomDocument_dump_file() |
| DomDocument_dump_mem_file | DomDocument_dump_file() |
| DomDocument_add_root | DomDocument_create_element() followed by DomNode_append_child() |
| DomDocument_dtd | DomDocument_doctype() |
| DomDocument_root | DomDocument_document_element() |
| DomDocument_children | DomNode_child_nodes() |
| DomDocument_imported_node | No replacement. |
| DomNode_add_child | Create a new node with e.g. DomDocument_create_element() und add it with DomNode_append_child(). |
| DomNode_children | DomNode_child_nodes() |
| DomNode_parent | DomNode_parent_node() |
| DomNode_new_child | Create a new node with e.g. DomDocument_create_element() and add it with DomNode_append_child(). |
| DomNode_set_content | Create a new node with e.g. DomDocument_create_text_node() and add it with DomNode_append_child(). |
| DomNode_get_content | Content is just a text node and can be accessed with DomNode_child_nodes(). |
| DomNode_set_content | Content is just a text node and can be added with DomNode_append_child(). |
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.
Table 2. XML constants
| Constant | Value | Description |
|---|---|---|
| XML_ELEMENT_NODE (integer) | 1 | Node is an element |
| XML_ATTRIBUTE_NODE (integer) | 2 | Node is an attribute |
| XML_TEXT_NODE (integer) | 3 | Node is a piece of text |
| XML_CDATA_SECTION_NODE (integer) | 4 | |
| XML_ENTITY_REF_NODE (integer) | 5 | |
| XML_ENTITY_NODE (integer) | 6 | Node is an entity like |
| XML_PI_NODE (integer) | 7 | Node is a processing instruction |
| XML_COMMENT_NODE (integer) | 8 | Node is a comment |
| XML_DOCUMENT_NODE (integer) | 9 | Node is a document |
| XML_DOCUMENT_TYPE_NODE (integer) | 10 | |
| XML_DOCUMENT_FRAG_NODE (integer) | 11 | |
| XML_NOTATION_NODE (integer) | 12 | |
| XML_GLOBAL_NAMESPACE (integer) | 1 | |
| XML_LOCAL_NAMESPACE (integer) | 2 | |
| XML_HTML_DOCUMENT_NODE (integer) | ||
| XML_DTD_NODE (integer) | ||
| XML_ELEMENT_DECL_NODE (integer) | ||
| XML_ATTRIBUTE_DECL_NODE (integer) | ||
| XML_ENTITY_DECL_NODE (integer) | ||
| XML_NAMESPACE_DECL_NODE (integer) | ||
| XML_ATTRIBUTE_CDATA (integer) | ||
| XML_ATTRIBUTE_ID (integer) | ||
| XML_ATTRIBUTE_IDREF (integer) | ||
| XML_ATTRIBUTE_IDREFS (integer) | ||
| XML_ATTRIBUTE_ENTITY (integer) | ||
| XML_ATTRIBUTE_NMTOKEN (integer) | ||
| XML_ATTRIBUTE_NMTOKENS (integer) | ||
| XML_ATTRIBUTE_ENUMERATION (integer) | ||
| XML_ATTRIBUTE_NOTATION (integer) | ||
| XPATH_UNDEFINED (integer) | ||
| XPATH_NODESET (integer) | ||
| XPATH_BOOLEAN (integer) | ||
| XPATH_NUMBER (integer) | ||
| XPATH_STRING (integer) | ||
| XPATH_POINT (integer) | ||
| XPATH_RANGE (integer) | ||
| XPATH_LOCATIONSET (integer) | ||
| XPATH_USERS (integer) | ||
| XPATH_NUMBER (integer) |
Classes
The API of the module follows the DOM Level 2 standard as closely as possible. Consequently, the API is fully object-oriented. It is a good idea to have the DOM standard available when using this module. Though the API is object-oriented, there are many functions which can be called in a non-object-oriented way by passing the object to operate on as the first argument. These functions are mainly to retain compatibility to older versions of the extension, and should not be used when creating new scripts.
This API differs from the official DOM API in two ways. First, all class attributes are implemented as functions with the same name. Secondly, the function names follow the PHP naming convention. This means that a DOM function lastChild() will be written as last_child().
This module defines a number of classes, which are listed — including their method — in the following tables. Classes with an equivalent in the DOM standard are named DOMxxx.
Table 3. List of classes
| Class name | Parent classes |
|---|---|
| DomAttribute | DomNode |
| DomCData | DomNode |
| DomComment | DomCData : DomNode |
| DomDocument | DomNode |
| DomDocumentType | DomNode |
| DomElement | DomNode |
| DomEntity | DomNode |
| DomEntityReference | DomNode |
| DomProcessingInstruction | DomNode |
| DomText | DomCData : DomNode |
| Parser | Currently still called DomParser |
| XPathContext |
Table 4. DomDocument class (DomDocument : DomNode)
| Method name | Function name | Remark |
|---|---|---|
| doctype | DomDocument_doctype() | |
| document_elemnent | DomDocument_document_element() | |
| create_element | DomDocument_create_element() | |
| create_text_node | DomDocument_create_text_node() | |
| create_comment | DomDocument_create_comment() | |
| create_cdata_section | DomDocument_create_cdata_section() | |
| create_processing_instruction | DomDocument_create_processing_instruction() | |
| create_attribute | DomDocument_create_attribute() | |
| create_entity_reference | DomDocument_create_entity_reference() | |
| get_elements_by_tagname | DomDocument_get_elements_by_tagname() | |
| get_element_by_id | DomDocument_get_element_by_id() | |
| dump_mem | DomDocument_dump_mem() | not DOM standard |
| dump_file | DomDocument_dump_file() | not DOM standard |
| html_dump_mem | DomDocument_html_dump_mem() | not DOM standard |
| xpath_init | xpath_init | not DOM standard |
| xpath_new_context | xpath_new_context | not DOM standard |
| xptr_new_context | xptr_new_context | not DOM standard |
Table 5. DomElement class (DomElement : DomNode)
| Method name | Function name | Remark |
|---|---|---|
| tagname | DomElement_tagname() | |
| get_attribute | DomElement_get_attribute() | |
| set_attribute | DomElement_set_attribute() | |
| remove_attribute | DomElement_remove_attribute() | |
| get_attribute_node | DomElement_get_attribute_node() | |
| get_elements_by_tagname | DomElement_get_elements_by_tagname() | |
| has_attribute | DomElement_has_attribute() |
Table 6. DomNode class
| Method name | Remark |
|---|---|
| DomNode_node_name() | |
| DomNode_node_value() | |
| DomNode_node_type() | |
| DomNode_last_child() | |
| DomNode_first_child() | |
| DomNode_child_nodes() | |
| DomNode_previous_sibling() | |
| DomNode_next_sibling() | |
| DomNode_parent_node() | |
| DomNode_owner_document() | |
| DomNode_insert_before() | |
| DomNode_append_child() | |
| DomNode_append_sibling() | Not in DOM standard. This function emulates the former behaviour of DomNode_append_child(). |
| DomNode_remove_child() | |
| DomNode_has_child_nodes() | |
| DomNode_has_attributes() | |
| DomNode_clone_node() | |
| DomNode_attributes() | |
| DomNode_unlink_node() | Not in DOM standard |
| DomNode_replace_node() | Not in DOM standard |
| DomNode_set_content() | Not in DOM standard, deprecated |
| DomNode_get_content() | Not in DOM standard, deprecated |
| DomNode_dump_node() | Not in DOM standard |
| DomNode_is_blank_node() | Not in DOM standard |
Table 7. DomAttribute class (DomAttribute : DomNode)
| Method name | Remark | |
|---|---|---|
| name | DomAttribute_name() | |
| value | DomAttribute_value() | |
| specified | DomAttribute_specified() |
Table 8. DomProcessingInstruction class (DomProcessingInstruction : DomNode)
| Method name | Function name | Remark |
|---|---|---|
| target | DomProcessingInstruction_target() | |
| data | DomProcessingInstruction_data() |
Table 10. XPathContext class
| Method name | Function name | Remark |
|---|---|---|
| eval | XPathContext_eval() | |
| eval_expression | XPathContext_eval_expression() | |
| register_ns | XPathContext_register_ns() |
Table 11. DomDocumentType class (DomDocumentType : DomNode)
| Method name | Function name | Remark |
|---|---|---|
| name | DomDocumentType_name() | |
| entities | DomDocumentType_entities() | |
| notations | DomDocumentType_notations() | |
| public_id | DomDocumentType_public_id() | |
| system_id | DomDocumentType_system_id() | |
| internal_subset | DomDocumentType_internal_subset() |
The classes DomDtd is derived from DomNode. DomComment is derived from DomCData.
Examples
Many examples in this reference require an XML string. Instead of repeating this string in every example, it will be put into a file which will be included by each example. This include file is shown in the following example section. Alternatively, you could create an XML document and read it with DomDocument_open_file().
- Table of Contents
- DomAttribute->name -- Returns name of attribute
- DomAttribute->specified -- Checks if attribute is specified
- DomAttribute->value -- Returns value of attribute
- DomDocument->add_root [deprecated] -- Adds a root node
- DomDocument->create_attribute -- Create new attribute
- DomDocument->create_cdata_section -- Create new cdata node
- DomDocument->create_comment -- Create new comment node
- DomDocument->create_element_ns -- Create new element node with an associated namespace
- DomDocument->create_element -- Create new element node
- DomDocument->create_entity_reference --
- DomDocument->create_processing_instruction -- Creates new PI node
- DomDocument->create_text_node -- Create new text node
- DomDocument->doctype -- Returns the document type
- DomDocument->document_element -- Returns root element node
- DomDocument->dump_file -- Dumps the internal XML tree back into a file
- DomDocument->dump_mem -- Dumps the internal XML tree back into a string
- DomDocument->get_element_by_id -- Searches for an element with a certain id
- DomDocument->get_elements_by_tagname --
- DomDocument->html_dump_mem -- Dumps the internal XML tree back into a string as HTML
- DomDocument->xinclude -- Substitutes XIncludes in a DomDocument Object.
- DomDocumentType->entities -- Returns list of entities
- DomDocumentType->internal_subset -- Returns internal subset
- DomDocumentType->name -- Returns name of document type
- DomDocumentType->notations -- Returns list of notations
- DomDocumentType->public_id -- Returns public id of document type
- DomDocumentType->system_id -- Returns system id of document type
- DomElement->get_attribute_node -- Returns value of attribute
- DomElement->get_attribute -- Returns value of attribute
- DomElement->get_elements_by_tagname -- Gets elements by tagname
- DomElement->has_attribute -- Checks to see if attribute exists
- DomElement->remove_attribute -- Removes attribute
- DomElement->set_attribute -- Adds new attribute
- DomElement->tagname -- Returns name of element
- DomNode->add_namespace -- Adds a namespace declaration to a node.
- DomNode->append_child -- Adds new child at the end of the children
- DomNode->append_sibling -- Adds new sibling to a node
- DomNode->attributes -- Returns list of attributes
- DomNode->child_nodes -- Returns children of node
- DomNode->clone_node -- Clones a node
- DomNode->dump_node -- Dumps a single node
- DomNode->first_child -- Returns first child of node
- DomNode->get_content -- Gets content of node
- DomNode->has_attributes -- Checks if node has attributes
- DomNode->has_child_nodes -- Checks if node has children
- DomNode->insert_before -- Inserts new node as child
- DomNode->is_blank_node -- Checks if node is blank
- DomNode->last_child -- Returns last child of node
- DomNode->next_sibling -- Returns the next sibling of node
- DomNode->node_name -- Returns name of node
- DomNode->node_type -- Returns type of node
- DomNode->node_value -- Returns value of a node
- DomNode->owner_document -- Returns the document this node belongs to
- DomNode->parent_node -- Returns the parent of the node
- DomNode->prefix -- Returns name space prefix of node
- DomNode->previous_sibling -- Returns the previous sibling of node
- DomNode->remove_child -- Removes child from list of children
- DomNode->replace_child -- Replaces a child
- DomNode->replace_node -- Replaces node
- DomNode->set_content -- Sets content of node
- DomNode->set_name -- Sets name of node
- DomNode->set_namespace -- Sets namespace of a node.
- DomNode->unlink_node -- Deletes node
- DomProcessingInstruction->data -- Returns data of pi node
- DomProcessingInstruction->target -- Returns target of pi node
- DomXsltStylesheet->process -- Applies the XSLT-Transformation on a DomDocument Object.
- DomXsltStylesheet->result_dump_file -- Dumps the result from a XSLT-Transformation into a file
- DomXsltStylesheet->result_dump_mem -- Dumps the result from a XSLT-Transformation back into a string
- domxml_new_doc -- Creates new empty XML document
- domxml_open_file -- Creates a DOM object from XML file
- domxml_open_mem -- Creates a DOM object of an XML document
- domxml_version -- Get XML library version
- domxml_xmltree -- Creates a tree of PHP objects from an XML document
- domxml_xslt_stylesheet_doc -- Creates a DomXsltStylesheet Object from a DomDocument Object.
- domxml_xslt_stylesheet_file -- Creates a DomXsltStylesheet Object from a xsl document in a file.
- domxml_xslt_stylesheet -- Creates a DomXsltStylesheet Object from a xml document in a string.
- xpath_eval_expression -- Evaluates the XPath Location Path in the given string
- xpath_eval -- Evaluates the XPath Location Path in the given string
- xpath_new_context -- Creates new xpath context
- xptr_eval -- Evaluate the XPtr Location Path in the given string
- xptr_new_context -- Create new XPath Context