XML更改值，其中attribute是

Question

With PHP I want to change the value in the node where attribute is something I specify. The XML file:

 <?xml version='1.0' standalone='yes'?> <days> <Maandag id="1">0</Maandag> <Dinsdag id="2">0</Dinsdag> <Woensdag id="3">0</Woensdag> <Donderdag id="4">0</Donderdag> <Vrijdag id="5">0</Vrijdag> <Zaterdag id="6">0</Zaterdag> <Zonday id="0">0</Zonday> </days> 

For example: Today is Monday so jddayofweek(0) = 1 Then the value of the node with id=1 needs to change, so in the end we get:

 <?xml version='1.0' standalone='yes'?> <days> <Maandag id="1">3</Maandag> <Dinsdag id="2">0</Dinsdag> <Woensdag id="3">0</Woensdag> <Donderdag id="4">0</Donderdag> <Vrijdag id="5">0</Vrijdag> <Zaterdag id="6">0</Zaterdag> <Zonday id="0">0</Zonday> </days> 

How do I do this in PHP?

Answer 1

You could change it using DOMdocument and DOMpath Just change the xml filename, data.xml (2x). Set $select and $changeTo .

<?php 

//Set your variables
$select = 1; //id you'd like to change
$changeTo = 3; //value you would like to change to

//Creating a new DOMDocument
$xmlDoc = new DOMDocument();

//from file
$xmlDoc->load("data.xml");

//Creating a new DOMPath
$Xpath = new DOMXPath($xmlDoc);

//the query selects all Matches any element node (*) that have a "id" attribute with a value of $select
$results = $Xpath->query('*[@id=' . $select . ']');

//Change node
$results->item(0)->nodeValue = $changeTo;

//Save document
$xmlDoc->save("data.xml");

echo "Edited document saved!"

?>

Answer 2

I'd recommend simpleXML , because it is - well - simple :

$xml = simplexml_load_string($x); // assume XML in $x
$id = 1; 

$day = $xml->xpath("*[@id=`$id`]")[0];
$day[0] = 5;

see the result:

echo $xml->asXML();

Comments:

• the xpath -expression will select the day by $id and give back an array of SimpleXML -elements.
• select the 1st element (index [0] ) and store it in $day (requires PHP >= 5.4)

see it working: https://eval.in/388827

Thinking further

If you make that XML, add clarity and flexibility by making it like this:

<days>
    <day name="Maandag" id="1">0</day>
    <day name="Dinsdag" id="2">0</day>
    <etc />
</days>

Answer 3

If your files are always small and similar content (like your example) you could preg_replace() them (or maybe str_replace())...the best solution is to write your own XML parser, which is a good rite-of-passage for all programmers.

http://php.net/manual/en/book.xml.php