simplexml_import_dom

(PHP 5, PHP 7)

simplexml_import_dom — Get a SimpleXMLElement object from a DOM node.

说明

SimpleXMLElement simplexml_import_dom ( DOMNode $node [, string $class_name = "SimpleXMLElement" ] )

This function takes a node of a DOM document and makes it into a SimpleXML node. This new object can then be used as a native SimpleXML element.

参数

node

A DOM Element node

class_name

You may use this optional parameter so that simplexml_import_dom() will return an object of the specified class. That class should extend the SimpleXMLElement class.

返回值

Returns a SimpleXMLElement 或者在失败时返回 FALSE.

Warning

此函数可能返回布尔值 FALSE，但也可能返回等同于 FALSE 的非布尔值。请阅读 布尔类型章节以获取更多信息。应使用 === 运算符来测试此函数的返回值。

范例

Example #1 Importing DOM

<?php
$dom = new DOMDocument;
$dom->loadXML('<books><book><title>blah</title></book></books>');
if (!$dom) {
    echo 'Error while parsing the document';
    exit;
}

$s = simplexml_import_dom($dom);

echo $s->book[0]->title;
?>

以上例程会输出：

blah

参见

User Contributed Notes

shirkaen at gmail dot com 11-Nov-2016 03:58
/*If tags in DOM have text and some part of this text is surrounded by other tag, simple_import_dom object doesn't contain position of child tag, so rendering it back to html/xml can be a problem. Printing such a node is also peculiar. Eg.*/

//////////////////////
$text = "<body><p>Some text before <em>italic </em>and after text.</p></body>";
$dom = new DOMDocument;
$dom->loadHTML($text);
$result = simplexml_import_dom($dom);
echo $result->p;

//////////////////////
//Prints :
//Some text before and after text.

print_r($result->p);
//Prints:
//SimpleXMLElement Object ( [em] => italic )

print_r($result->p->em)
//does more or less the same:
//SimpleXMLElement Object ( [0] => italic )

var_dump($result->p);
//Prints:
//object(SimpleXMLElement)#8 (1) { ["em"]=> string(7) "italic " }

var_dump($result->p->em)
//object(SimpleXMLElement)#9 (1) { [0]=> string(7) "italic " }

//but
echo $result->p->em;
//prints:
//italic
brandonkirsch at perceptionilluminates dot com 15-Aug-2013 12:38
simplexml_import_dom() will accept DOMNodes or other SimpleXMLElements.  This has a useful purpose if you are extending the SimpleXMLElement class and would prefer the xpath() method to return your class extension instead of basic SimpleXMLElements.  For example:

class MySimpleXML extends SimpleXMLElement{
    public function xpath($xpath){
        $return = array();
        $simpleXmls = parent::xpath($xpath); // run SimpleXMLElement xpath, returning an array of SimpleXMLElements
        foreach($simpleXmls as $xml){
            $return[] = simplexml_import_dom($xml,'MySimpleXML'); // copy SimpleXMLElement, returning as MySimpleXML instance
        }
        return $return;
    }
}

Now I can create an instance of MySimpleXML, run an xpath, and get my results back as an array of MySimpleXML elements instead of the native SimpleXMLElement:

$mySimpleXml = new mySimpleXml('<root><node/></root>');

$array = $mySimpleXml->xpath('/root/node'); // returns array with a single MySimpleXml object