Based on the following XML I want to retrieve the product name and image of a certain node (ID)
<?xml version="1.0" encoding="utf-8"?>
<clients>
<client id="A">
<product>Name of product A</product>
<image>Product image name A</image>
</client>
<client id="B">
<product>Name of product B</product>
<image>Product image name B</image>
</client>
</clients>
This is the PHP Code:
$doc = DOMDocument::load('clients.xml');
$xpath = new DOMXPath($doc);
$query = '//client[#id="A"]';
$info = $xpath->query($query);
If I do $info->item(0)->nodeValue I get both information together and not individually:
Name of product A
Product image name A
But I want to get ->product->nodeValue and image->nodeValue based on the client ID.
How can I do that? Doing $info->item(0)->product->nodeValue for example doesn't work.
->item(0)->nodeValue gives everything inside that particular item (in this case 0)
You use XPath to fetch the nodes. The result of an XPath location path is a list of node. ->item(0) returns the first node in this list.This is the client element node.
Calling DOMElement:$nodeValue always returns all descendent text nodes as a string. In you case the text nodes inside the product and the image element nodes.
You will have the to fetch the child nodes if you want the values separately.
$dom = new DOMDocument();
$dom->loadXML($xml);
$xpath = new DOMXpath($dom);
foreach ($xpath->evaluate('//client[#id="A"]/*[self::product or self::image]') as $child) {
echo $child->localName, ': ', $child->nodeValue, "\n";
}
Output:
product: Name of product A
image: Product image name A
Your result returns a single node (client). The nodevalue of that node is all of the text underneath it.
Try:
"//client [#id='A']/*[name()='product' or name()='image']" would return two nodes. Remember to check the name if you want to use them by position.
Related
I have this PHP I found in a Q&A forum that queries an XML file:
$doc = new DOMDocument; // Create a new dom document
$doc->preserveWhiteSpace = false; // Set features
$doc->formatOutput = true; // Create indents on xml
$doc->Load('i.xml'); // Load the file
$xpath = new DOMXPath($doc);
$query = '//users/user/firstname[.= "'.$_POST["search"].'"]'; // The xpath (starts from root node)
$names = $xpath->query($query); // A list of matched elements
$Output="";
foreach ($names as $node) {
$Output.=$doc->saveXML($node->parentNode)."\n"; // We get the parent of "<firstname>" element (the entire "<user>" node and its children) (maybe get the parent node directly using xpath)
// and use the saveXML() to convert it to string
}
echo $Output."<br>\n\n"; // The result
echo "<hr><br><b>Below view the results as HTML content. (See also the page's HTML code):</b>\n<pre>".htmlspecialchars($Output)."</pre>";
The script will search the values of all the firstname nodes in the XML document from the input from the POST, and will return the parent node of the nodefirstname, if the POST input value matches any of the node values.
This script works well, but it only returns queries that contain the entire value of a firstname node, and will not work if I search for a substring of the node's text (e.g a query for Potato will return Potato, but a query for Pot, will not give me results for Potato).
So how do you get a result that only contains a substring of the node's text, instead of the entire value ?
I have an XML file with a root, a parent node and some inner nodes. If I use DOM->load(myxmlfile.xml) is it possible to traverse through the nodes and remove the imageurlnode?
I have tried this example:
$doc = new DOMDocument;
$doc->load('myxmlfile.xml');
$book = $doc->documentElement;
// we retrieve the chapter and remove it from the book
$node = $book->getElementsByTagName('imageurl')->item(0);
$oldnode = $book->removeChild($chapter);
echo $doc->saveXML();
But this only removes items from underneath root. My XML has the following structure:
<root>
<property>
<imageurl></imageurl>
</property
</root>
So when it comes to removing the imgurl node (as it's inside a parent inside the root) how would I remove it?
If you have the node, say $chapter, just use its parent to delete it
$chapter->parentNode->removeChild($chapter);
I want to completely remove the size="id" attribute from every <door> element.
<?xml version="1.0" encoding="UTF-8"?>
<doors>
<door id="1" entry="3249" size="30"/>
<door id="1041" entry="6523" size="3094"/>
-- and 1000 more....
</doors>
The PHP code:
$xml = new SimpleXMLElement('http://mysite/doors.xml', NULL, TRUE);
$ids_to_delete = array( 1, 1506 );
foreach ($ids_to_delete as $id) {
$result = $xml->xpath( "//door[#size='$id']" );
foreach ( $result as $node ) {
$dom = dom_import_simplexml($node);
$dom->parentNode->removeChild($dom);
}
}
$xml->saveXml();
I get no errors but it does not delete the size attribute. Why?
I get no errors but it does not delete the size attribute. Why?
There are mulitple reasons why it does not delete the size attribute. The one that popped first into my mind was that attributes are no child nodes. Using a method to remove a child does just not fit to remove an attribute.
Each element node has an associated set of attribute nodes; the element is the parent of each of these attribute nodes; however, an attribute node is not a child of its parent element.
From: Attribute Nodes - XML Path Language (XPath), bold by me.
However, you don't see an error here, because the $result you have is an empty array. You just don't select any nodes to remove - neither elements nor attributes - with your xpath. That is because there is no such element you look for:
//door[#size='1']
You're searching for the id in the size attribute: No match.
These are the reasons why you get no errors and it does not delete any size attribute: 1.) you don't delete attributes here, 2.) you don't query any elements to delete attributes from.
How to delete attributes in SimpleXML queried by Xpath?
You can remove the attribute nodes by selecting them with an Xpath query and then unset the SimpleXMLElement self-reference:
// all size attributes of all doors
$result = $xml->xpath("//door/#size");
foreach ($result as $node) {
unset($node[0]);
}
In this example, all attribute nodes are queried by the Xpath expressions that are size attributes of door elements (which is what you ask for in your question) and then those are removed from the XML.
//door/#size
(see Abbreviated Syntax)
Now here the full example:
<?php
/**
* #link https://eval.in/215817
*/
$buffer = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<doors>
<door id="1" entry="3249" size="30"/>
<door id="1041" entry="6523" size="3094"/>
-- and 1000 more....
</doors>
XML;
$xml = new SimpleXMLElement($buffer);
// all size attributes of all doors
$result = $xml->xpath("//door/#size");
foreach ($result as $node) {
unset($node[0]);
}
$xml->saveXml("php://output");
Output (Online Demo):
<?xml version="1.0" encoding="UTF-8"?>
<doors>
<door id="1" entry="3249"/>
<door id="1041" entry="6523"/>
-- and 1000 more....
</doors>
You can do your whole query in DOMDocument using DOMXPath, rather than switching between SimpleXML and DOM:
$dom = new DOMDocument;
$dom->load('my_xml_file.xml');
# initialise an XPath object to act on the $dom object
$xp = new DOMXPath( $dom );
# run the query
foreach ($xp->query( "//door[#size]" ) as $door) {
# remove the attribute
$door->removeAttribute('size');
}
print $dom->saveXML();
Output for the input you supplied:
<?xml version="1.0" encoding="UTF-8"?>
<doors>
<door id="1" entry="3249"/>
<door id="1041" entry="6523"/>
</doors>
If you do want only to remove the size attribute for the IDs in your list, you should use the code:
foreach ($ids_to_delete as $id) {
# searches for elements with a matching ID and a size attribute
foreach ($xp->query("//door[#id='$id' and #size]") as $door) {
$door->removeAttribute('size');
}
}
Your code wasn't working for several reasons:
it looks like your XPath was wrong, since your array is called $ids_to_delete and your XPATH is looking for door elements with the size attribute equal to the value from $ids_to_delete;
you're converting the nodes to DOMDocument objects ($dom = dom_import_simplexml($node);) to do the deletion, but $xml->saveXml();, which I presume you printed somehow, is a SimpleXML object;
you need to remove the element attribute; removeChild removes the whole element.
I have next type of XML:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE test SYSTEM "dtd">
<root>
<tag1>
<1>Name</1>
<2>Num1</2>
<3>NumOrder</3>
<4>test</5>
<6>line</6>
<7>HTTP </7>
<8>1</8>
<9></9>
</tag1>
<tag2>
<1>Name</1>
<2>Num1</2>
<3>NumOrder</3>
<4>test</5>
<6>line</6>
<7>HTTP </7>
<8>1</8>
<9></9>
</tag2>
...
<tagN>
<1>Name</1>
<2>Num1</2>
<3>NumOrder</3>
<4>test</5>
<6>line</6>
<7>HTTP </7>
<8>1</8>
<9></9>
</tagN>
</root>
And i need to get root with each child element separately in array saved as HTML:
array = [rootwithchild1,rootwithchild2...N];
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE test SYSTEM "dtd">
<root>
<tagN>
<1>Name</1>
<2>Num1</2>
<3>NumOrder</3>
<4>test</5>
<6>line</6>
<7>HTTP </7>
<8>1</8>
<9></9>
</tagN>
</root>
For now i make 2 doms, in one i get all child separately, in another i have deleted all child and left only root. At these step i wanted to add each child to root, save as html, delete child, and so on with each child, but this doesn't work.
$bodyNode = $copydoc->getElementsByTagName('root')->item(0);
foreach ($mini as $value) {
$bodyNode->appendChild($value);
$result[] = $copydoc->saveHTML();
$bodyNode->removeChild($value);
}
Error on $bodyNode->appendChild($value);
Mini is array of cut child.
Lib: $doc = new DOMDocument();
Can anyone advice how to do this right, maybe better to use xpath or something else..?
Thanks
I would simply create a new document that contains only the root element and a “fake” initial child:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE test SYSTEM "dtd">
<root>
<fakechild />
</root>
After that, loop over the child elements of the original document – and for each of those perform the following steps:
import the child node from the original document into the new document using DOMDocument::importNode
replace the current child node of the root element of the new document with the imported node using DOMNode::replaceChild with the firstChild of the root element as second parameter
save the new document
(Having the <fakechild /> in the root element to begin with is not technically necessary, a simple whitespace text node should do as well – but with an empty root element this would not work in such a straight fashion, because the firstChild would give you NULL in the first loop iteration, so you would not have a node to feed to DOMNode::replaceChild as second parameter. Of course you could do additional checks for that and use appendChild instead of replaceChild for the first item … but why complicate stuff more than necessary.)
DOMNode::getElemementsByTagName() returns a live result. So if you remove the node from the DOM it is removed from the node list as well.
You can iterate the list backwards...
for ($i = $nodes->length - 1; $i >= 0; $i--) {
$node = $nodes->item($i);
...
}
... or copy it to an array:
foreach (iterator_to_array($nodes) as $node) {
...
}
Node lists from DOMXpath::evaluate() are not affected that way. XPath allows a more specific selection of nodes, too.
$xpath = new DOMXpath($domDocument);
$nodes = $xpath->evaluate('/root/*');
foreach (iterator_to_array($nodes) as $node) {
...
}
But I wonder why are you modifying (destroying) the original XML source?
If would create a new document to act as a template and. Never removing nodes, only creating new documents and importing them:
// load the original source
$source= new DOMDocument();
$source->loadXml($xml);
$xpath = new DOMXpath($source);
// create a template dom
$template = new DOMDocument();
$parent = $template;
// add a node and all its ancestors to the template
foreach ($xpath->evaluate('/root/part[1]/ancestor-or-self::*') as $node) {
$parent = $parent->appendChild($template->importNode($node, FALSE));
}
// for each of the child element nodes
foreach ($xpath->evaluate('/root/part/*') as $node) {
// create a new target
$target = new DOMDocument();
// import the nodes from the template
$target->appendChild($target->importNode($template->documentElement, TRUE));
// find the first element node that has no child element nodes
$targetXpath = new DOMXpath($target);
$targetNode = $targetXpath->evaluate('//*[count(*) = 0]')->item(0);
// append the child node from the original xml
$targetNode->appendChild($target->importNode($node, TRUE));
echo $target->saveXml(), "\n\n";
}
Demo: https://eval.in/191304
Hello I know there is many questions here about those three topics combined together to update XML entries, but it seems everyone is very specific to a given problem.
I have been spending some time trying to understand XPath and its way, but I still can't get what I need to do.
Here we go
I have this XML file
<?xml version="1.0" encoding="UTF-8"?>
<storagehouse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="schema.xsd">
<item id="c7278e33ef0f4aff88da10dfeeaaae7a">
<name>HDMI Cable 3m</name>
<weight>0.5</weight>
<category>Cables</category>
<location>B3</location>
</item>
<item id="df799fb47bc1e13f3e1c8b04ebd16a96">
<name>Dell U2410</name>
<weight>2.5</weight>
<category>Monitors</category>
<location>C2</location>
</item>
</storagehouse>
What I would like to do is to update/edit any of the nodes above when I need to. I will do a Html form for that.
But my biggest conserne is how do I find and update a the desired node and update it?
Here I have some of what I am trying to do
<?php
function fnDOMEditElementCond()
{
$dom = new DOMDocument();
$dom->load('storage.xml');
$library = $dom->documentElement;
$xpath = new DOMXPath($dom);
// I kind of understand this one here
$result = $xpath->query('/storagehouse/item[1]/name');
//This one not so much
$result->item(0)->nodeValue .= ' Series';
// This will remove the CDATA property of the element.
//To retain it, delete this element (see delete eg) & recreate it with CDATA (see create xml eg).
//2nd Way
//$result = $xpath->query('/library/book[author="J.R.R.Tolkein"]');
// $result->item(0)->getElementsByTagName('title')->item(0)->nodeValue .= ' Series';
header("Content-type: text/xml");
echo $dom->saveXML();
}
?>
Could someone maybe give me an examples with attributes and so on, so one a user decides to update a desired node, I could find that node with XPath and then update it?
The following example is making use of simplexml which is a close friend of DOMDocument. The xpath shown is the same regardless which method you use, and I use simplexml here to keep the code low. I'll show a more advanced DOMDocument example later on.
So about the xpath: How to find the node and update it. First of all how to find the node:
The node has the element/tagname item. You are looking for it inside the storagehouse element, which is the root element of your XML document. All item elements in your document are expressed like this in xpath:
/storagehouse/item
From the root, first storagehouse, then item. Divided with /. You already know that, so the interesting part is how to only take those item elements that have the specific ID. For that the predicate is used and added at the end:
/storagehouse/item[#id="id"]
This will return all item elements again, but this time only those which have the attribute id with the value id (string). For example in your case with the following XML:
$xml = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<storagehouse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="schema.xsd">
<item id="c7278e33ef0f4aff88da10dfeeaaae7a">
<name>HDMI Cable 3m</name>
<weight>0.5</weight>
<category>Cables</category>
<location>B3</location>
</item>
<item id="df799fb47bc1e13f3e1c8b04ebd16a96">
<name>Dell U2410</name>
<weight>2.5</weight>
<category>Monitors</category>
<location>C2</location>
</item>
</storagehouse>
XML;
that xpath:
/storagehouse/item[#id="df799fb47bc1e13f3e1c8b04ebd16a96"]
will return the computer monitor (because such an item with that id exists). If there would be multiple items with the same id value, multiple would be returned. If there were none, none would be returned. So let's wrap that into a code-example:
$simplexml = simplexml_load_string($xml);
$result = $simplexml->xpath(sprintf('/storagehouse/item[#id="%s"]', $id));
if (!$result || count($result) !== 1) {
throw new Exception(sprintf('Item with id "%s" does not exists or is not unique.', $id));
}
list($item) = $result;
In this example, $titem is the SimpleXMLElement object of that computer monitor xml element name item.
So now for the changes, which are extremely easy with SimpleXML in your case:
$item->category = 'LCD Monitor';
And to finally see the result:
echo $simplexml->asXML();
Yes that's all with SimpleXML in your case.
If you want to do this with DOMDocument, it works quite similar. However, for updating an element's value, you need to access the child element of that item as well. Let's see the following example which first of all fetches the item as well. If you compare with the SimpleXML example above, you can see that things not really differ:
$doc = new DOMDocument();
$doc->loadXML($xml);
$xpath = new DOMXPath($doc);
$result = $xpath->query(sprintf('/storagehouse/item[#id="%s"]', $id));
if (!$result || $result->length !== 1) {
throw new Exception(sprintf('Item with id "%s" does not exists or is not unique.', $id));
}
$item = $result->item(0);
Again, $item contains the item XML element of the computer monitor. But this time as a DOMElement. To modify the category element in there (or more precisely it's nodeValue), that children needs to be obtained first. You can do this again with xpath, but this time with an expression relative to the $item element:
./category
Assuming that there always is a category child-element in the item element, this could be written as such:
$category = $xpath->query('./category', $item)->item(0);
$category does now contain the first category child element of $item. What's left is updating the value of it:
$category->nodeValue = "LCD Monitor";
And to finally see the result:
echo $doc->saveXML();
And that's it. Whether you choose SimpleXML or DOMDocument, that depends on your needs. You can even switch between both. You probably might want to map and check for changes:
$repository = new Repository($xml);
$item = $repository->getItemByID($id);
$item->category = 'LCD Monitor';
$repository->saveChanges();
echo $repository->getXML();
Naturally this requires more code, which is too much for this answer.