class Html in Service Container 7.2
Same name and namespace in other branches
- 7 lib/Drupal/Component/Utility/Html.php \Drupal\Component\Utility\Html
Provides DOMDocument helpers for parsing and serializing HTML strings.
Hierarchy
- class \Drupal\Component\Utility\Html
Expanded class hierarchy of Html
File
- lib/
Drupal/ Component/ Utility/ Html.php, line 15 - Contains \Drupal\Component\Utility\Html.
Namespace
Drupal\Component\UtilityView source
class Html {
/**
* An array of previously cleaned HTML classes.
*
* @var array
*/
protected static $classes = array();
/**
* An array of the initial IDs used in one request.
*
* @var array
*/
protected static $seenIdsInit;
/**
* An array of IDs, including incremented versions when an ID is duplicated.
* @var array
*/
protected static $seenIds;
/**
* Stores whether the current request was sent via AJAX.
*
* @var bool
*/
protected static $isAjax = FALSE;
/**
* Prepares a string for use as a valid class name.
*
* Do not pass one string containing multiple classes as they will be
* incorrectly concatenated with dashes, i.e. "one two" will become "one-two".
*
* @param string $class
* The class name to clean.
*
* @return string
* The cleaned class name.
*/
public static function getClass($class) {
if (!isset(static::$classes[$class])) {
static::$classes[$class] = static::cleanCssIdentifier(Unicode::strtolower($class));
}
return static::$classes[$class];
}
/**
* Prepares a string for use as a CSS identifier (element, class, or ID name).
*
* http://www.w3.org/TR/CSS21/syndata.html#characters shows the syntax for
* valid CSS identifiers (including element names, classes, and IDs in
* selectors.)
*
* @param string $identifier
* The identifier to clean.
* @param array $filter
* An array of string replacements to use on the identifier.
*
* @return string
* The cleaned identifier.
*/
public static function cleanCssIdentifier($identifier, array $filter = array(
' ' => '-',
'_' => '-',
'/' => '-',
'[' => '-',
']' => '',
)) {
// We could also use strtr() here but its much slower than str_replace(). In
// order to keep '__' to stay '__' we first replace it with a different
// placeholder after checking that it is not defined as a filter.
$double_underscore_replacements = 0;
if (!isset($filter['__'])) {
$identifier = str_replace('__', '##', $identifier, $double_underscore_replacements);
}
$identifier = str_replace(array_keys($filter), array_values($filter), $identifier);
// Replace temporary placeholder '##' with '__' only if the original
// $identifier contained '__'.
if ($double_underscore_replacements > 0) {
$identifier = str_replace('##', '__', $identifier);
}
// Valid characters in a CSS identifier are:
// - the hyphen (U+002D)
// - a-z (U+0030 - U+0039)
// - A-Z (U+0041 - U+005A)
// - the underscore (U+005F)
// - 0-9 (U+0061 - U+007A)
// - ISO 10646 characters U+00A1 and higher
// We strip out any character not in the above list.
$identifier = preg_replace('/[^\\x{002D}\\x{0030}-\\x{0039}\\x{0041}-\\x{005A}\\x{005F}\\x{0061}-\\x{007A}\\x{00A1}-\\x{FFFF}]/u', '', $identifier);
// Identifiers cannot start with a digit, two hyphens, or a hyphen followed by a digit.
$identifier = preg_replace(array(
'/^[0-9]/',
'/^(-[0-9])|^(--)/',
), array(
'_',
'__',
), $identifier);
return $identifier;
}
/**
* Sets if this request is an Ajax request.
*
* @param bool $is_ajax
* TRUE if this request is an Ajax request, FALSE otherwise.
*/
public static function setIsAjax($is_ajax) {
static::$isAjax = $is_ajax;
}
/**
* Prepares a string for use as a valid HTML ID and guarantees uniqueness.
*
* This function ensures that each passed HTML ID value only exists once on
* the page. By tracking the already returned ids, this function enables
* forms, blocks, and other content to be output multiple times on the same
* page, without breaking (X)HTML validation.
*
* For already existing IDs, a counter is appended to the ID string.
* Therefore, JavaScript and CSS code should not rely on any value that was
* generated by this function and instead should rely on manually added CSS
* classes or similarly reliable constructs.
*
* Two consecutive hyphens separate the counter from the original ID. To
* manage uniqueness across multiple Ajax requests on the same page, Ajax
* requests POST an array of all IDs currently present on the page, which are
* used to prime this function's cache upon first invocation.
*
* To allow reverse-parsing of IDs submitted via Ajax, any multiple
* consecutive hyphens in the originally passed $id are replaced with a
* single hyphen.
*
* @param string $id
* The ID to clean.
*
* @return string
* The cleaned ID.
*/
public static function getUniqueId($id) {
// If this is an Ajax request, then content returned by this page request
// will be merged with content already on the base page. The HTML IDs must
// be unique for the fully merged content. Therefore use unique IDs.
if (static::$isAjax) {
return static::getId($id) . '--' . Crypt::randomBytesBase64(8);
}
// @todo Remove all that code once we switch over to random IDs only,
// see https://www.drupal.org/node/1090592.
if (!isset(static::$seenIdsInit)) {
static::$seenIdsInit = array();
}
if (!isset(static::$seenIds)) {
static::$seenIds = static::$seenIdsInit;
}
$id = static::getId($id);
// Ensure IDs are unique by appending a counter after the first occurrence.
// The counter needs to be appended with a delimiter that does not exist in
// the base ID. Requiring a unique delimiter helps ensure that we really do
// return unique IDs and also helps us re-create the $seen_ids array during
// Ajax requests.
if (isset(static::$seenIds[$id])) {
$id = $id . '--' . ++static::$seenIds[$id];
}
else {
static::$seenIds[$id] = 1;
}
return $id;
}
/**
* Prepares a string for use as a valid HTML ID.
*
* Only use this function when you want to intentionally skip the uniqueness
* guarantee of self::getUniqueId().
*
* @param string $id
* The ID to clean.
*
* @return string
* The cleaned ID.
*
* @see self::getUniqueId()
*/
public static function getId($id) {
$id = str_replace([
' ',
'_',
'[',
']',
], [
'-',
'-',
'-',
'',
], Unicode::strtolower($id));
// As defined in http://www.w3.org/TR/html4/types.html#type-name, HTML IDs can
// only contain letters, digits ([0-9]), hyphens ("-"), underscores ("_"),
// colons (":"), and periods ("."). We strip out any character not in that
// list. Note that the CSS spec doesn't allow colons or periods in identifiers
// (http://www.w3.org/TR/CSS21/syndata.html#characters), so we strip those two
// characters as well.
$id = preg_replace('/[^A-Za-z0-9\\-_]/', '', $id);
// Removing multiple consecutive hyphens.
$id = preg_replace('/\\-+/', '-', $id);
return $id;
}
/**
* Resets the list of seen IDs.
*/
public static function resetSeenIds() {
static::$seenIds = NULL;
}
/**
* Normalizes an HTML snippet.
*
* This function is essentially \DOMDocument::normalizeDocument(), but
* operates on an HTML string instead of a \DOMDocument.
*
* @param string $html
* The HTML string to normalize.
*
* @return string
* The normalized HTML string.
*/
public static function normalize($html) {
$document = static::load($html);
return static::serialize($document);
}
/**
* Parses an HTML snippet and returns it as a DOM object.
*
* This function loads the body part of a partial (X)HTML document and returns
* a full \DOMDocument object that represents this document.
*
* Use \Drupal\Component\Utility\Html::serialize() to serialize this
* \DOMDocument back to a string.
*
* @param string $html
* The partial (X)HTML snippet to load. Invalid markup will be corrected on
* import.
*
* @return \DOMDocument
* A \DOMDocument that represents the loaded (X)HTML snippet.
*/
public static function load($html) {
$document = <<<EOD
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /></head>
<body>!html</body>
</html>
EOD;
// PHP's \DOMDocument serialization adds extra whitespace when the markup
// of the wrapping document contains newlines, so ensure we remove all
// newlines before injecting the actual HTML body to be processed.
$document = strtr($document, array(
"\n" => '',
'!html' => $html,
));
$dom = new \DOMDocument();
// Ignore warnings during HTML soup loading.
@$dom
->loadHTML($document);
return $dom;
}
/**
* Converts the body of a \DOMDocument back to an HTML snippet.
*
* The function serializes the body part of a \DOMDocument back to an (X)HTML
* snippet. The resulting (X)HTML snippet will be properly formatted to be
* compatible with HTML user agents.
*
* @param \DOMDocument $document
* A \DOMDocument object to serialize, only the tags below the first <body>
* node will be converted.
*
* @return string
* A valid (X)HTML snippet, as a string.
*/
public static function serialize(\DOMDocument $document) {
$body_node = $document
->getElementsByTagName('body')
->item(0);
$html = '';
if ($body_node !== NULL) {
foreach ($body_node
->getElementsByTagName('script') as $node) {
static::escapeCdataElement($node);
}
foreach ($body_node
->getElementsByTagName('style') as $node) {
static::escapeCdataElement($node, '/*', '*/');
}
foreach ($body_node->childNodes as $node) {
$html .= $document
->saveXML($node);
}
}
return $html;
}
/**
* Adds comments around a <!CDATA section in a \DOMNode.
*
* \DOMDocument::loadHTML() in \Drupal\Component\Utility\Html::load() makes
* CDATA sections from the contents of inline script and style tags. This can
* cause HTML4 browsers to throw exceptions.
*
* This function attempts to solve the problem by creating a
* \DOMDocumentFragment to comment the CDATA tag.
*
* @param \DOMNode $node
* The element potentially containing a CDATA node.
* @param string $comment_start
* (optional) A string to use as a comment start marker to escape the CDATA
* declaration. Defaults to '//'.
* @param string $comment_end
* (optional) A string to use as a comment end marker to escape the CDATA
* declaration. Defaults to an empty string.
*/
public static function escapeCdataElement(\DOMNode $node, $comment_start = '//', $comment_end = '') {
foreach ($node->childNodes as $child_node) {
if ($child_node instanceof \DOMCdataSection) {
$embed_prefix = "\n<!--{$comment_start}--><![CDATA[{$comment_start} ><!--{$comment_end}\n";
$embed_suffix = "\n{$comment_start}--><!]]>{$comment_end}\n";
// Prevent invalid cdata escaping as this would throw a DOM error.
// This is the same behavior as found in libxml2.
// Related W3C standard: http://www.w3.org/TR/REC-xml/#dt-cdsection
// Fix explanation: http://en.wikipedia.org/wiki/CDATA#Nesting
$data = str_replace(']]>', ']]]]>< |
Modifiers | Type | Description | Overrides |
|---|---|---|---|---|
|
Html:: |
protected static | property | An array of previously cleaned HTML classes. | |
|
Html:: |
protected static | property | Stores whether the current request was sent via AJAX. | |
|
Html:: |
protected static | property | An array of IDs, including incremented versions when an ID is duplicated. | |
|
Html:: |
protected static | property | An array of the initial IDs used in one request. | |
|
Html:: |
public static | function | Prepares a string for use as a CSS identifier (element, class, or ID name). | |
|
Html:: |
public static | function | Decodes all HTML entities including numerical ones to regular UTF-8 bytes. | |
|
Html:: |
public static | function | Escapes text by converting special characters to HTML entities. | |
|
Html:: |
public static | function | Adds comments around a <!CDATA section in a \DOMNode. | |
|
Html:: |
public static | function | Prepares a string for use as a valid class name. | |
|
Html:: |
public static | function | Prepares a string for use as a valid HTML ID. | |
|
Html:: |
public static | function | Prepares a string for use as a valid HTML ID and guarantees uniqueness. | |
|
Html:: |
public static | function | Parses an HTML snippet and returns it as a DOM object. | |
|
Html:: |
public static | function | Normalizes an HTML snippet. | |
|
Html:: |
public static | function | Resets the list of seen IDs. | |
|
Html:: |
public static | function | Converts the body of a \DOMDocument back to an HTML snippet. | |
|
Html:: |
public static | function | Sets if this request is an Ajax request. |