DOMNode::hasChildNodes()

(PHP 5, PHP 7)

Checks if node has children

说明

publicDOMNode::hasChildNodes(void): bool

This function checks if the node has children.

返回值

成功时返回TRUE，或者在失败时返回FALSE。

参见

• DOMNode::hasAttributes() Checks if node has attributes

Personally I think using a simple:[code]if($DOMNode->childNodes <>0){}[/code] works better.

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

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

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?

<?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
- - - - - - - - - - - - - -