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.

示例

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'];
        }
    }
}
?>

以上示例会输出：

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

SimpleXMLElement::count() - Counts the children of an element
count() - 统计数组、Countable 对象中所有元素的数量

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用户贡献的备注 4 notes

down

aero ¶

17 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

down

Sebastian ¶

19 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.

down

transglobe at gmx dot de ¶

16 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...)

down

boan dot web at outlook dot com ¶

5 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
?>