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PHP - Manual: DOMNode::hasChildNodes

2024-12-23

DOMNode::hasChildNodes

(PHP 5, PHP 7, PHP 8)

DOMNode::hasChildNodes Checks if node has children

说明

public DOMNode::hasChildNodes(): bool

This function checks if the node has children.

参数

此函数没有参数。

返回值

成功时返回 true, 或者在失败时返回 false

参见

add a noteadd a note

User Contributed Notes 5 notes

up
7
sansana
11 years ago
Personally I think using a simple:[code]if($DOMNode->childNodes <>0){}[/code] works better.
up
5
richard dot gildx at gmail dot com
9 years ago
This "hasChildNodes()" exercise is simple enough to make it clear and understandable. Or, you could take it as a tag empty check. By Richard Holm, Sweden.

<?php
$xmldoc
=
'<?xml version="1.0" ?>
<root>
<text>Text</text>
<none/>
<empty></empty>
<space> </space>
</root>'
;

$domdoc=new DOMDocument();
$domdoc->loadXML($xmldoc);

$tag=$domdoc->getElementsByTagName('root')->item(0);
$v=$tag->hasChildNodes()?" hasChildNodes":" hasNoChildNodes";
echo
$tag->tagName.$v."<br/>";

$tag=$domdoc->getElementsByTagName('text')->item(0);
$v=$tag->hasChildNodes()?" hasChildNodes":" hasNoChildNodes";
echo
$tag->tagName.$v."<br/>";

$tag=$domdoc->getElementsByTagName('none')->item(0);
$v=$tag->hasChildNodes()?" hasChildNodes":" hasNoChildNodes";
echo
$tag->tagName.$v."<br/>";

$tag=$domdoc->getElementsByTagName('empty')->item(0);
$v=$tag->hasChildNodes()?" hasChildNodes":" hasNoChildNodes";
echo
$tag->tagName.$v."<br/>";

$tag=$domdoc->getElementsByTagName('space')->item(0);
$v=$tag->hasChildNodes()?" hasChildNodes":" hasNoChildNodes";
echo
$tag->tagName.$v."<br/>";
?>

Output:
root hasChildNodes
text hasChildNodes
none hasNoChildNodes
empty hasNoChildNodes
space hasChildNodes
up
6
syngcw at syncgw.com
12 years ago
This function is a bit tricky. If you want to find XML childnodes it is useless. You need to create a work-around:

<?php

$x
= new DOMDocument();
$x->loadXML('
<A>
<B>b-text</B>
<C>
  <D>d-text</D>
</C>
<E/>
</A>'
);

shownode($x->getElementsByTagName('A')->item(0));
function
shownode($x) {
foreach (
$x->childNodes as $p)
  if (
hasChild($p)) {
      echo
$p->nodeName.' -> CHILDNODES<br>';
     
shownode($p);
  } elseif (
$p->nodeType == XML_ELEMENT_NODE)
   echo
$p->nodeName.' '.$p->nodeValue.'<br>';
}
function
hasChild($p) {
if (
$p->hasChildNodes()) {
  foreach (
$p->childNodes as $c) {
   if (
$c->nodeType == XML_ELEMENT_NODE)
    return
true;
  }
}
return
false;
}

?>

shows:
B b-text
C -> CHILDNODES
D d-text
E
up
-6
Anonymous
7 years ago
Hi what if its a dynamic file and we cannot use get elements by tag name then how do we print the contents of all level tags?
up
-9
jintoppy at gmail dot com
13 years ago
<?php

$doc
= new DOMDocument;
$node = $doc->createElement("FirstMain", "First Main Node. This have child");
$doc->appendChild($node);
$childnode = $doc->createElement("childnode", "child node");
$node->appendChild($childnode);
$secondnode = $doc->createElement("SecondMain", "First Main Node. This don't have child");
$doc->appendChild($secondnode);
$doc->saveXML();
$nodeElmt = $doc->getElementsByTagName("FirstMain");
/*
if given as $nodeElmt = $doc->getElementsByTagName("childnode");
the output would be "This node has childnodes"

if given as $nodeElmt = $doc->getElementsByTagName("SecondMain");
the output would be "This node has no childnodes"

*/

foreach($nodeElmt as $nodeElmt)
{
if(
$nodeElmt->hasChildNodes())
{
echo
"This node has childnodes";
}
else
{
echo
"This node has no childnodes";
}
}

 
?>

- - - - - - - - - - - - - -

Output:

This node has childnodes

- - - - - - - - - - - - - -

官方地址:https://www.php.net/manual/en/domnode.haschildnodes.php

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