How to write CDATA using SimpleXmlElement?

问题:

I have this code to create and update xml file:

<?php
$xmlFile    = 'config.xml';
$xml        = new SimpleXmlElement('<site/>');
$xml->title = 'Site Title';
$xml->title->addAttribute('lang', 'en');
$xml->saveXML($xmlFile);
?>

This generates the following xml file:

<?xml version="1.0"?>
<site>
  <title lang="en">Site Title</title>
</site>

The question is: is there a way to add CDATA with this method/technique to create xml code below?

<?xml version="1.0"?>
<site>
  <title lang="en"><![CDATA[Site Title]]></title>
</site>

回答1:

Got it! I adapted the code from this great solution:

<?php
// http://coffeerings.posterous.com/php-simplexml-and-cdata
class SimpleXMLExtended extends SimpleXMLElement {
  public function addCData($cdata_text) {
    $node = dom_import_simplexml($this); 
    $no   = $node->ownerDocument; 
    $node->appendChild($no->createCDATASection($cdata_text)); 
  } 
}

$xmlFile    = 'config.xml';
// instead of $xml = new SimpleXMLElement('<site/>');
$xml        = new SimpleXMLExtended('<site/>');
$xml->title = NULL; // VERY IMPORTANT! We need a node where to append
$xml->title->addCData('Site Title');
$xml->title->addAttribute('lang', 'en');
$xml->saveXML($xmlFile);
?>

XML file generated:

<?xml version="1.0"?>
<site>
  <title lang="en"><![CDATA[Site Title]]></title>
</site>

Thank you Petah

回答2:

Here's my version of this class that has a quick addChildWithCDATA method, based on your answer:

    Class SimpleXMLElementExtended extends SimpleXMLElement {

  /**
   * Adds a child with $value inside CDATA
   * @param unknown $name
   * @param unknown $value
   */
  public function addChildWithCDATA($name, $value = NULL) {
    $new_child = $this->addChild($name);

    if ($new_child !== NULL) {
      $node = dom_import_simplexml($new_child);
      $no   = $node->ownerDocument;
      $node->appendChild($no->createCDATASection($value));
    }

    return $new_child;
  }
}

Simply use it like that:

$node = new SimpleXMLElementExtended();
$node->addChildWithCDATA('title', 'Text that can contain any unsafe XML charachters like & and <>');

回答3:

You can also create a helper function for this, if you'd rather not extend SimpleXMLElement:

 /**
  * Adds a CDATA property to an XML document.
  *
  * @param string $name
  *   Name of property that should contain CDATA.
  * @param string $value
  *   Value that should be inserted into a CDATA child.
  * @param object $parent
  *   Element that the CDATA child should be attached too.
  */
 $add_cdata = function($name, $value, &$parent) {
   $child = $parent->addChild($name);

   if ($child !== NULL) {
     $child_node = dom_import_simplexml($child);
     $child_owner = $child_node->ownerDocument;
     $child_node->appendChild($child_owner->createCDATASection($value));
   }

   return $child;
 };

回答4:

    class MySimpleXMLElement extends SimpleXMLElement{

        public function addChildWithCData($name , $value) {
            $new = parent::addChild($name);
            $base = dom_import_simplexml($new);
            $docOwner = $base->ownerDocument;
            $base->appendChild($docOwner->createCDATASection($value));
        }

    }

        $simpleXmlElemntObj = new MySimpleXMLElement('<site/>');

        /* USAGE */

        /* Standard */
        $simpleXmlElemntObj->addChild('Postcode','1111');

       /* With CDATA */
       $simpleXmlElemntObj->addChildWithCData('State','Processing');


    /* RESULT */
    /*
    <?xml version="1.0"?>
    <site>
        <Postcode>1111</Postcode>
        <State><![CDATA[Processing]]></State>
    </site>
   */

回答5:

Here is my combined solution with adding child with CDATA or adding CDATA to the node.

class SimpleXMLElementExtended extends SimpleXMLElement
{
    /**
    * Add value as CData to a given XML node
    *
    * @param SimpleXMLElement $node SimpleXMLElement object representing the child XML node
    * @param string $value A text to add as CData
    * @return void
    */
    private function addCDataToNode(SimpleXMLElement $node, $value = '')
    {
        if ($domElement = dom_import_simplexml($node))
        {
            $domOwner = $domElement->ownerDocument;
            $domElement->appendChild($domOwner->createCDATASection("{$value}"));
        }
    }

    /**
    * Add child node with value as CData
    *
    * @param string $name The child XML node name to add
    * @param string $value A text to add as CData
    * @return SimpleXMLElement
    */
    public function addChildWithCData($name = '', $value = '')
    {
        $newChild = parent::addChild($name);
        if ($value) $this->addCDataToNode($newChild, "{$value}");
        return $newChild;
    }

    /**
    * Add value as CData to the current XML node 
    *
    * @param string $value A text to add as CData
    * @return void
    */
    public function addCData($value = '')
    {
        $this->addCDataToNode($this, "{$value}");
    }
}

// Usage example:

$xml_doc = '<?xml version="1.0" encoding="utf-8"?>
<offers xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1">
</offers>';

$xml = new SimpleXMLElementExtended($xml_doc);

$offer = $xml->addChild('o');
$offer->addAttribute('id', $product->product_id);
$offer->addAttribute('url', 'some url');

$cat = $offer->addChildWithCData('cat', 'Category description as CDATA');

// or

$cat = $offer->addChild('cat');
$cat->addCData('Category description as CDATA');