SimpleXMLElement::children

(PHP 5, PHP 7, PHP 8)

SimpleXMLElement::children — Finds children of given node

说明

public SimpleXMLElement::children(?string $namespaceOrPrefix = null, bool $isPrefix = false): ?SimpleXMLElement

This method finds the children of an element. The result follows normal iteration rules.

注意: SimpleXML 建起了一个给大多数方法添加迭代属性的规则。不能通过使用 var_dump() 或任何可检查对象的其它东西来查看。

参数

namespaceOrPrefix

An XML namespace.

isPrefix

If isPrefix is true, namespaceOrPrefix will be regarded as a prefix. If false, namespaceOrPrefix will be regarded as a namespace URL.

返回值

Returns a SimpleXMLElement element, whether the node has children or not, unless the node represents an attribute, in which case null is returned.

范例

示例 #1 Traversing a children() pseudo-array

<?php
$xml = new SimpleXMLElement(
'<person>
 <child role="son">
  <child role="daughter"/>
 </child>
 <child role="daughter">
  <child role="son">
   <child role="son"/>
  </child>
 </child>
</person>');

foreach ($xml->children() as $second_gen) {
    echo ' The person begot a ' . $second_gen['role'];

    foreach ($second_gen->children() as $third_gen) {
        echo ' who begot a ' . $third_gen['role'] . ';';

        foreach ($third_gen->children() as $fourth_gen) {
            echo ' and that ' . $third_gen['role'] .
                ' begot a ' . $fourth_gen['role'];
        }
    }
}
?>

以上例程会输出：

The person begot a son who begot a daughter; The person
begot a daughter who begot a son; and that son begot a son

示例 #2 Using namespaces

<?php
$xml = '<example xmlns:foo="my.foo.urn">
  <foo:a>Apple</foo:a>
  <foo:b>Banana</foo:b>
  <c>Cherry</c>
</example>';

$sxe = new SimpleXMLElement($xml);

$kids = $sxe->children('foo');
var_dump(count($kids));

$kids = $sxe->children('foo', TRUE);
var_dump(count($kids));

$kids = $sxe->children('my.foo.urn');
var_dump(count($kids));

$kids = $sxe->children('my.foo.urn', TRUE);
var_dump(count($kids));

$kids = $sxe->children();
var_dump(count($kids));
?> 
int(0)
int(2)
int(2)
int(0)
int(1)

参见

add a noteadd a note

User Contributed Notes 15 notes

up
12
aero
15 years ago
Here's a simple, recursive, function to transform XML data into pseudo E4X syntax ie. root.child.value = foobar

<?php
error_reporting(E_ALL);

$xml = new SimpleXMLElement(
'<Patriarch>
   <name>Bill</name>
   <wife>
     <name>Vi</name>
   </wife>
   <son>
     <name>Bill</name>
   </son>
   <daughter>
     <name>Jeri</name>
     <husband>
       <name>Mark</name>
     </husband>
     <son>
       <name>Greg</name>
     </son>
     <son>
       <name>Tim</name>
     </son>    
     <son>
       <name>Mark</name>
     </son>    
     <son>
       <name>Josh</name>
         <wife>
           <name>Kristine</name>
         </wife>
         <son>
           <name>Blake</name>
         </son>
         <daughter>
           <name>Liah</name>
         </daughter>
     </son>
   </daughter>
</Patriarch>');

RecurseXML($xml);

function RecurseXML($xml,$parent="")
{
   $child_count = 0;
   foreach($xml as $key=>$value)
   {
      $child_count++;    
      if(RecurseXML($value,$parent.".".$key) == 0)  // no childern, aka "leaf node"
      {
         print($parent . "." . (string)$key . " = " . (string)$value . "<BR>\n");       
      }    
   }
   return $child_count;
}

?>

The output....

.name = Bill
.wife.name = Vi
.son.name = Bill
.daughter.name = Jeri
.daughter.husband.name = Mark
.daughter.son.name = Greg
.daughter.son.name = Tim
.daughter.son.name = Mark
.daughter.son.name = Josh
.daughter.son.wife.name = Kristine
.daughter.son.son.name = Blake
.daughter.son.daughter.name = Liah
up
7
Sebastian
16 years ago
Just a quick addition:

If you need to access a child node which contains a dash, you need to encapsulate it with {""}.

For example:
<?php
foreach ($domain->domain-listing as $product) {
}
?>

The example above doesn't work because of the dash. But instead you need to use:
<?php
foreach ($domain->{"domain-listing"} as $product) {
}
?>

At least for me the second example works perfectly fine.
up
2
transglobe at gmx dot de
14 years ago
I made a slightly differnt approch towards the RecurseXML function. Beeing hungry I had problems with the code, as it did just overwrite two <maincourse>s. So here is what I did:

<?php

$xml = new SimpleXMLElement(
'<meal>
   <type>Lunch</type>
   <time>12:30</time>
   <menu>
     <entree>salad</entree>
     <maincourse>
        <part>ships</part>
        <part>steak</part>
     </maincourse>
     <maincourse>
        <part>fisch</part>
        <part>rice</part>
     </maincourse>
     <maincourse>
        <part>wine</part>
        <part>cheese</part>
     </maincourse>
   </menu>
</meal>');

$vals = array();
RecurseXML($xml,$vals);

foreach($vals as $key=>$value)
  print("{$key} = {$value}<BR>\n");

function RecurseXML($xml,&$vals,$parent="") {

  $childs=0;
  $child_count=-1; # Not realy needed.
  $arr=array();
        foreach ($xml->children() as $key=>$value) {
                if (in_array($key,$arr)) {
                        $child_count++;
                } else {
                        $child_count=0;
                }
                $arr[]=$key;
                $k=($parent == "") ? "$key.$child_count" : "$parent.$key.$child_count";
                $childs=RecurseXML($value,$vals,$k);
                if ($childs==0) {
                        $vals[$k]= (string)$value;
                }
        }

  return $childs;
}

?>
Output is like this:
type.0 = Lunch
time.0 = 12:30
menu.0.entree.0 = salad
menu.0.maincourse.0.part.0 = ships
menu.0.maincourse.0.part.1 = steak
menu.0.maincourse.0 =
menu.0.maincourse.1.part.0 = fisch
menu.0.maincourse.1.part.1 = rice
menu.0.maincourse.1 =
menu.0.maincourse.2.part.0 = wine
menu.0.maincourse.2.part.1 = cheese
menu.0.maincourse.2 =
menu.0 =

(Not beautiful, but it solved my case...)
up
0
boan dot web at outlook dot com
3 years ago
SimpleXMLElement::children can return null in this case:

<?php
$xml = '
<root attr="Hello"/>
';

$sxe = new SimpleXMLElement($xml);

$sxe_xpath = $sxe->xpath('/root/@attr')[0];

$children = $sxe_xpath->children();

var_export($children); // Is null
?>
up
0
coldshine1 at rambler dot ru
11 years ago
This is my recursive simple function to parse XML with attributes.

<?php
function ParseXML($node, &$parent=array(), $only_child=true) {        

        //Current node name
        $node_name = $node->getName();
         
        //Let's count children
        $only_child = true;
        if($node->count() > 1 ) $only_child = false;

        //If there is no child, then there may be text data
        if($only_child){
            $content="$node";           
            if (strlen($content)>0) $parent['content']=$content;
        }
       
        //Get attributes of current node
        foreach ($node->attributes() as $k=>$v) {
            $parent['@attributes'][$k]="$v";
        }
      
        //Get children
        $count = 0;
        foreach ($node->children() as $child_name=>$child_node) {
            if(!$only_child) //If there are siblings then we'll add node to the end of the array
                LGServerPVR::ParseXML($child_node, $parent[$node_name][$child_name][$count], $only_child);
            else
                LGServerPVR::ParseXML($child_node, $parent[$node_name][$child_name], $only_child);
            $count++;
        }
       
        return $parent; 
        //(c) c01d[s]h!nE 10.12.2010      
    }

?>
up
0
mrdaniellee at live dot com
12 years ago
use this If you want to view the HTML as well as data.

normal dumps display the parsed versions of HTML.
This code displays the HTML as Text in a Text Area, and also display all other a data along side as an array

perfect for debugging (xml with html).

Try This Code:

<?php
$xml  = simplexml_load_file($url);

function xml2array_parse($xml){
     foreach ($xml->children() as $parent => $child){
         $return["$parent"] = xml2array_parse($child)?xml2array_parse($child):"$child";
     }
     return $return;
}

print "<pre><textarea style=\"width:200%;height:100%;\">";
print_r(xml2array_parse($xml));
print "</textarea></pre>";
?>
up
0
Anonymous
13 years ago
for XML namespaces such as <dc:creator> in RSS feeds use

<?php
    $xml = new SimpleXMLElement($string);
    $item = $xml->channel[0]->item[0];
    $dc = $item->children("http://purl.org/dc/elements/1.1/");
    echo $dc->creator;
?>
up
-1
Anonymous
11 years ago
Here's my xml-to-array routine. Unlike many of the other comments here, this one takes namespaces into account.

<?php

class XmlArray {

  public function load_dom ($xml) {
    $node=simplexml_import_dom($xml);
    return $this->add_node($node);
  }
 
  public function load_string ($s) {
    $node=simplexml_load_string($s);
    return $this->add_node($node);
  }
 
  private function add_node ($node, &$parent=null, $namespace='', $recursive=false) {

    $namespaces = $node->getNameSpaces(true);
    $content="$node";
   
    $r['name']=$node->getName();
    if (!$recursive) {
      $tmp=array_keys($node->getNameSpaces(false));
      $r['namespace']=$tmp[0];
      $r['namespaces']=$namespaces;
    }
    if ($namespace) $r['namespace']=$namespace;
    if ($content) $r['content']=$content;
   
    foreach ($namespaces as $pre=>$ns) {
      foreach ($node->children($ns) as $k=>$v) {
        $this->add_node($v, $r['children'], $pre, true);
      }
      foreach ($node->attributes($ns) as $k=>$v) {
        $r['attributes'][$k]="$pre:$v";
      }
    }
    foreach ($node->children() as $k=>$v) {
      $this->add_node($v, $r['children'], '', true);
    }
    foreach ($node->attributes() as $k=>$v) {
      $r['attributes'][$k]="$v";
    }
   
    $parent[]=&$r;
    return $parent[0];
   
  }

}

?>
up
-1
thetazzbot at gmail dot com
10 years ago
Ok so say you have this xml:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<!DOCTYPE nitf
PUBLIC "-//IPTC-NAA//DTD NITF 3.1//EN"
       "http://www.nitf.org/site/nitf-documentation/nitf-3-1.dtd">
<nitf>
  <head>
    <docdata management-status="embargoed">
      <!--data/2011/08/23/parties/doc4e53aa5783cca930694817.txt-->
      <doc-id id-string="doc4e53aa5783cca930694817"/>
      <date.release norm="20110823T000000"/>
      <key-list/>
    </docdata>
    <pubdata type="web" position.section="parties" position.sequence="0"/>
  </head>

-- snip --

If you need to access the nodes named "like.this" such as the date.release above, here is how I did it:

$xml = new SimpleXMLElement($xhtml);
echo (string)$xml->head->docdata->{"date.release"}["norm"];

Took me a while to figure that one out ;)
up
-1
taylorbarstow at that google mail thingy
16 years ago
Sometimes you actually want an array, not a pseudo array.   This is especially true when you aren't dealing with attributes (i.e., you just want the array of child nodes).

Do like this:

<?php
$children = $sxml->xpath('child::node()');
?>

The reason you might want this is to be able to use array functions like array_shift, array_pop, etc.  This is especially true when you are writing recursive functions.  Simplexml works really well in iterative programming, but if you try to implement recursion it gets ugly.
up
-1
Andrew Rose (rose dot andrew at gmail dot com)
17 years ago
The example below shows the basic use of depth-first recursion to span the xml tree.

This is coded for the command line, and it prints out the original sentance above and then the copy cat sentence it creates itself for comparison, which as you will see; this example is slightly off from, I'll leave it upto you to resolve this issue.

All in all I personaly think xml and recursion go hand in hand, so if you don't understand recursion but know xml and want to use php to manipulate xml you will need to learn about recursion at some point.

<?php
$xml = simplexml_load_string(
'<person>
<child role="son">
  <child role="daughter"/>
</child>
<child role="daughter">
  <child role="son">
   <child role="son"/>
  </child>
</child>
</person>');

function recurse($child)
{
   foreach($child->children() as $children) {
     echo ' who begot a '.$children['role'];
     recurse($children);
   }
    return;
}

foreach($xml->children() as $children) {
echo 'The person begot a '.$children['role'];
  recurse($children, 0);
echo '; ';
}

echo "\n";
echo 'The person begot a son who begot a daughter; The person begot a daughter who begot a son; and that son begot a son'."\n";

?>
up
-2
zyxwvu at users dot sourceforge dot net
18 years ago
File:

<category>
  <item>text</item>
  <bold>text</bold>
  <item>text</item>
  <item>text</item>
  <mark>text</mark>
  <bold>text</bold>
</category>

If you want to get also names of the tags, you can use this loop layout:

<?php
foreach($category -> children() as $name => $node){
  echo $name.'<br/>';
}
?>
up
-2
rodmen at gmail dot com
13 years ago
Transform xml to array php

<?php
function xml2phpArray($xml,$arr){
    $iter = 0;
        foreach($xml->children() as $b){
                $a = $b->getName();
                if(!$b->children()){
                        $arr[$a] = trim($b[0]);
                }
                else{
                        $arr[$a][$iter] = array();
                        $arr[$a][$iter] = xml2phpArray($b,$arr[$a][$iter]);
                }
        $iter++;
        }
        return $arr;
}

$Array = simplexml_load_string(file_get_contents('myfile.xml'));
print_r(xml2phpArray($Array,array()));
?>
up
-2
no-one
17 years ago
For anyone who hasn't read Sterling Hughe's article (http://www.zend.com/php5/articles/php5-simplexml.php):

<?php
$xml_document =<<<EOT
<?xml version="1.0"?>
<root xmlns:foo="http://example.com">
  <foo:bar>baz</foo:bar>
</root>
EOT;

$xml_document = simplexml_load_xml($xml_document);

$foo_ns_bar = $xml_document->children('http://example.com');

echo $foo_ns_bar->bar[0]; // prints 'baz'
?>
up
-4
crescentfreshpot at yahoo dot com
14 years ago
Just a warning that the iterable returned from children() contains the '@attributes' key, which is "invisible" during a foreach but can be seen if using a different construct, such as list()=each() or casting to an array before iterating w/ foreach.
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