simplexml_load_file()

(PHP 5, PHP 7)

Interprets an XML file into an object

说明

simplexml_load_file(string $filename[,string $class_name= "SimpleXMLElement"[,int $options= 0[,string $ns= ""[,bool $is_prefix= FALSE]]]]): SimpleXMLElement

Convert the well-formed XML document in the given file to an object.

参数

$filename: Path to the XML file
Note:
Libxml 2 unescapes the URI, so if you want to pass e.g.b&cas the URI parametera, you have to callsimplexml_load_file(rawurlencode('http://example.com/?a='. urlencode('b&c'))). Since PHP 5.1.0 you don't need to do this because PHP will do it for you.
$class_name: You may use this optional parameter so that simplexml_load_file() will return an object of the specified class. That class should extend the SimpleXMLElement class.
$options: Since PHP 5.1.0 and Libxml 2.6.0, you may also use the$optionsparameter to specify additional Libxml parameters.
$ns: Namespace prefix or URI.
$is_prefix: TRUE if$nsis a prefix,FALSE if it's a URI; defaults to FALSE.

返回值

Returns an object of class SimpleXMLElement with properties containing the data held within the XML document,或者在失败时返回FALSE.

Warning
此函数可能返回布尔值FALSE，但也可能返回等同于FALSE的非布尔值。请阅读布尔类型章节以获取更多信息。应使用===运算符来测试此函数的返回值。

错误／异常

Produces an E_WARNING error message for each error found in the XML data.

Tip

Use libxml_use_internal_errors() to suppress all XML errors, and libxml_get_errors() to iterate over them afterwards.

范例

Example #1 Interpret an XML document

<?php
// The file test.xml contains an XML document with a root element
// and at least an element /[root]/title.
if (file_exists('test.xml')) {
    $xml = simplexml_load_file('test.xml');
 
    print_r($xml);
} else {
    exit('Failed to open test.xml.');
}
?>

This script will display, on success:

SimpleXMLElement Object
(
  [title] => Example Title
  ...
)

At this point, you can go about using$xml->titleand any other elements.

参见

simplexml_load_string()Interprets a string of XML into an object
SimpleXMLElement::__construct() Creates a new SimpleXMLElement object
Dealing with XML errors
libxml_use_internal_errors()Disable libxml errors and allow user to fetch error information as needed
Basic SimpleXML usage

Sometimes we have xml's with hyphens nodes, like
<my_xml>
 <some-node>value</some-node>
</my_xml>
You'll need to use
<?php
$simpleXmlObj->{'some-node'}
?>
instead of 
<?php
$simpleXmlObj->some-node;
?>

To correctly extract a value from a CDATA just make sure you cast the SimpleXML Element to a string value by using the cast operator:
<?php
$xml = '<?xml version="1.0" encoding="UTF-8" ?>
<rss>
  <channel>
    <item>
      <title><![CDATA[Tom & Jerry]]></title>
    </item>
  </channel>
</rss>';
$xml = simplexml_load_string($xml);
// echo does the casting for you
echo $xml->channel->item->title;
// but vardump (or print_r) not!
var_dump($xml->channel->item->title);
// so cast the SimpleXML Element to 'string' solve this issue
var_dump((string) $xml->channel->item->title);
?>
Above will output:
Tom & Jerry
object(SimpleXMLElement)#4 (0) {}
string(11) "Tom & Jerry"

// Be carefull if you migrate or use local machine
// for test/development.
// Windows directory separators: "\" and "/"
// You may mix separators "C:\somedir\www/img/bg.jpg".
// Mixed separators path work fine in other functions
// But simplexml_load_file() failed with mixed separators.
// Examples:
include("C:\dir\my.php");  // work (windows)
include("C:\dir/my.php");  // work (windows) with mixed
include("C:/dir/my.php");  // work (windows, linux)
simplexml_load_file("C:\dir\my.php");  // work
simplexml_load_file("C:\dir/my.php");  // failed with mixed
simplexml_load_file("C:/dir/my.php");  // work

Because the encoding of my XML file is UTF-8 and the 
encoding of my web page is iso-8859-1 I was getting strange characters such as â€™ instead of a right single quote.
The solution to this turned out to be hard to find, but really easy to implement.
http://uk3.php.net/manual/en/function.iconv.php
Using the iconv() function you can convert from one encodign to another, the TRANSLIT option seems to work best for what I needed. Here's my example:
<?php
// convert string from utf-8 to iso8859-1
$horoscope = iconv( "UTF-8", "ISO-8859-1//TRANSLIT", $horoscope );
?>
I found the solution on this page...
http://tinyurl.com/lm39xc
Hope this helps

if you want to check when this function fails,make sure to compare the return value with === instead of == :
<?php
$url = 'http://www.example.com';
$xml = simpleXML_load_file($url,"SimpleXMLElement",LIBXML_NOCDATA);
if($xml === FALSE)
{
  //deal with error
}
else { //do stuff } 
?>
Otherwise you may end up with FALSE all the time even if the document is ok. Hope this helps someone ;)

If you have some nodes which are having special characters, it would not load properly
for an instance see the nodes below
<node:number>1538-7445</node:number>
<node:coverDisplayDate>Sep 1 2012 12:00:00:000AM</node:coverDisplayDate>
either you have to change the : to other special characters like '-' in order to convert it properly
Correct Node
<node-number>1538-7445</node-number>
<node-coverDisplayDate>Sep 1 2012 12:00:00:000AM</node-coverDisplayDate>
I have wasted my precious time while debugging this. Please aware about this. ?

I stumbled on this: a single element with a simple string in it becomes a string, but a single element with a *space* in it becomes an Array, with one element, the string space.
I'm sure to XML mystics this is wise and wonderful but it really confused me, and I thought it might confuse others.
<?php
$parsed = simplexml_load_string('<container><space> </space><blank></blank><string>hello</string></container>');
$content = json_decode(json_encode($parsed),TRUE);
var_dump($content);
/* Output is:
array(3) {
 'space' => array(1) {      ← did NOT expect this!
  [0] => string(1) " "
 }
 'blank' => array(0) { }
 'string' => string(5) "hello"
}
 */

In case you have a XML file with a series of equally named elements on one level simplexml incorrectly processes them and doesn't allow to walk through the array using foreach(). As far as I'm concerned, it is the problem caused by PHP xml_parser (see: http://ru2.php.net/manual/ru/function.xml-parser-create.php#53188).
To avoid this, just use count() and walk through the array using for().
Example:
<params>
 <param>
  <name>version.shell</name>
  <value>1.0</value>
 </param>
 <param>
   <name>version.core</name>
   <value>1.0</value>
 </param>
 <param>
   <name>file.lang</name>
   <value>vc.lang</value>
 </param>
 ...
</params>
<?php
$filename = '...';
$xml = simplexml_load_file($filename);
$p_cnt = count($xml->param);
for($i = 0; $i < $p_cnt; $i++) {
 $param = $xml->param[$i];
 ...;
}
?>

If you want CDATA in your object you should use LIBXML_NOCDATA
<?php
$xml = simplexml_load_file($file_xml, 'SimpleXMLElement',LIBXML_NOCDATA);
  
  print_r($xml);
?>

In regards to Anonymous on 7th April 2006
There is a way to get back HTML tags. For example:
<?xml version="1.0"?>
<intro>
  Welcome to <b>Example.com</b>!
</intro>
<?php
// I use @ so that it doesn't spit out content of my XML in an error message if the load fails. The content could be passwords so this is just to be safe.
$xml = @simplexml_load_file('content_intro.xml');
if ($xml) {
  // asXML() will keep the HTML tags but it will also keep the parent tag <intro> so I strip them out with a str_replace. You could obviously also use a preg_replace if you have lots of tags.
  $intro = str_replace(array('<intro>', '</intro>'), '', $xml->asXML());
} else {
  $error = "Could not load intro XML file.";
}
?>
With this method someone can change the intro in content_intro.xml and ensure that the HTML is well formed and not ruin the whole site design.

Suppose you have loaded a XML file into $simpleXML_obj. 
The structure is like below :
SimpleXMLElement Object
(
  [node1] => SimpleXMLElement Object
    (
      [subnode1] => value1
      [subnode2] => value2
      [subnode3] => value3
    )
  [node2] => SimpleXMLElement Object
    (
      [subnode4] => value4
      [subnode5] => value5
      [subnode6] => value6
    )
)
When searching a specific node in the object, you may use this function :
    
<?php
  function &getXMLnode($object, $param) {
    foreach($object as $key => $value) {
      if(isset($object->$key->$param)) {
        return $object->$key->$param;
      }
      if(is_object($object->$key)&&!empty($object->$key)) {
        $new_obj = $object->$key;
        $ret = getCfgParam($new_obj, $param);  
      }
    }
    if($ret) return (string) $ret;
    return false;
  }
?>
So if you want to get subnode4 value you may use this function like this : 
<?php
$result = getXMLnode($simpleXML_obj, 'subnode4');
echo $result;
?>
It display "value4"

Be careful if you are using simplexml data directly to feed your MySQL database using MYSQLi and bind parameters. 
The data coming from simplexml are Objects and the bind parameters functions of MySQLi do NOT like that! (it causes some memory leak and can crash Apache/PHP)
In order to do this properly you MUST cast your values to the right type (string, integer...) before passing them to the binding methods of MySQLi.
I did not find that in the documentation and it caused me a lot of headache.

If you don't want that the CDATA values get escaped, just load the XML with LIBXML_NOCDATA as an 3rd argument.
Note: A PHP version >= 5.1.0 is required for this to work.
Example: 
<?php simplexml_load_file('xmldatei.xml', null, LIBXML_NOCDATA); ?>

If you are loading many files, this may slow down your page load time.
To set a timeout, use file_get_context and then simplexml_load_string
<?php
$fp = fopen('http://www.example.com/rss', false, stream_create_context(array('http' => array('timeout', '1.5'))));
if ($fp) {
  print_r( simplexml_load_string($fp) );
} else {
  echo "The request timed out";
}
?>

So it seems SimpleXML doesn't support CDATA... I bashed together this little regex function to sort out the CDATA before trying to parse XML with the likes of simplexml_load_file / simplexml_load_string. Hope it might help somebody and would be very interested to hear of better solutions. (Other than *not* using SimpleXML of course! ;)
It looks for any <![CDATA [Text and HTML etc in here]]> elements, htmlspecialchar()'s the encapsulated data and then strips the "<![CDATA [" and "]]>" tags out.
<?php
function simplexml_unCDATAise($xml) {
  $new_xml = NULL;
  preg_match_all("/\<\!\[CDATA \[(.*)\]\]\>/U", $xml, $args);
  if (is_array($args)) {
    if (isset($args[0]) && isset($args[1])) {
      $new_xml = $xml;
      for ($i=0; $i<count($args[0]); $i++) {
        $old_text = $args[0][$i];
        $new_text = htmlspecialchars($args[1][$i]);
        $new_xml = str_replace($old_text, $new_text, $new_xml);
      }
    }
  }
  return $new_xml;
}
//Usage:
$xml = 'Your XML with CDATA...';
$xml = simplexml_unCDATAise($xml);
$xml_object = simplexml_load_string($xml);
?>

Occasionally you may try to load a file and have it complain about an entity and throw a parser error.
If this is the case, check to make sure that the file in question does not contain an ampersand (&) without a corresponding entity reference.
If it does, or if you want to err on the side of caution, then instead of using simplexml_load_file, try this:
$file = file_get_contents('stuff.xml');
$temp = preg_replace('/&(?!(quot|amp|pos|lt|gt);)/', '&amp;', $file);
$xml = simplexml_load_string($temp) or die("xml not loading");
Read the file into a string, add 'amp;' after any '&' that is not part of a character entity, then parse the string as xml.

A wrapper around simplexml_load_file to circumvent nasty error messages when the xml server times out or gives a 500 error etc.
<?php
function loadXML2($domain, $path, $timeout = 30) {
  /*
    Usage:
    
    $xml = loadXML2("127.0.0.1", "/path/to/xml/server.php?code=do_something");
    if($xml) {
      // xml doc loaded
    } else {
      // failed. show friendly error message.
    }
  */
  $fp = fsockopen($domain, 80, $errno, $errstr, $timeout);
  if($fp) {
    // make request
    $out = "GET $path HTTP/1.1\r\n";
    $out .= "Host: $domain\r\n";
    $out .= "Connection: Close\r\n\r\n";
    fwrite($fp, $out);
    
    // get response
    $resp = "";
    while (!feof($fp)) {
      $resp .= fgets($fp, 128);
    }
    fclose($fp);
    // check status is 200
    $status_regex = "/HTTP\/1\.\d\s(\d+)/";
    if(preg_match($status_regex, $resp, $matches) && $matches[1] == 200) {  
      // load xml as object
      $parts = explode("\r\n\r\n", $resp);  
      return simplexml_load_string($parts[1]);        
    }
  }
  return false;
  
}
?>

If you find that you are receiving 500 errors with simplexml_load_file() but you can access the xml/rss feed manually through a browser, your script is probably being blocked by a user agent sniffer.
Add this code before your xml call to remedy this issue
<?php
ini_set("user_agent","Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)");
ini_set("max_execution_time", 0);
ini_set("memory_limit", "10000M");
$rss = simplexml_load_file($feed_url);
?>

Making SimpleXMLElement objects session save.
Besides the effect of not surviving sessions, the SimpleXMLElement object may even crash the session_start() function when trying to re-enter the session!
To come up with a solution for this, I used a pattern as follows. The core idea is to transform the SimpleXMLElement between session calls to and from a string representation which of course is session save.
<?php
 //
 // session save handling of SimpleXMLElement objects
 // (applies to/ tested with PHP 5.1.5 and PHP 5.2.1)
 // The myClass pattern allows for conveniently accessing
 // XML structures while being session save
 //
 class myClass
 {
  private $o_XMLconfig = null;
  private $s_XMLconfig = '';
  
  public function __construct($args_configfile)
  {
   $this->o_XMLconfig = simplexml_load_file($args_configfile);
   $this->s_XMLconfig = $this->o_XMLconfig->asXML();
  } // __construct()
  
  public function __destruct()
  {
   $this->s_XMLconfig = $this->o_XMLconfig->asXML();
   unset($this->o_XMLconfig); // this object would otherwise crash 
                 // the subsequent call of 
                 // session_start()!
  } // __destruct()
  
  public function __wakeup()
  {
   $this->o_XMLconfig = simplexml_load_string($this->s_XMLconfig);
  } // __wakeup()
  
 } // class myClass
?>

A little function very helpfull in using simplexml_load_file behind a proxy
<?php
function getXMLfromURL($url) {
   $Proxy = getenv("HTTP_PROXY");
   if (strlen($Proxy) > 1) {
    $r_default_context = stream_context_get_default ( array
          ('http' => array(
            'proxy' => $Proxy,
            'request_fulluri' => True,
          ),
        )
      );
    libxml_set_streams_context($r_default_context);
   }
   $daten = simplexml_load_file($url);
   return ($daten);
  }
?>
where HTTP_PROXY is set to e.g.: tcp://proxy:8080

What has been found when using the script is that simplexml_load_file() will remove any HTML formating inside the XML file, and will also only load so many layers deep. If your XML file is to deap, it will return a boolean false.

Get all tags and their values. (recursive)
<?php
$xml = simplexml_load_file('settings.xml');
function all_tag($xml){
  $i=0; $name = "";
  foreach ($xml as $k){
    $tag = $k->getName();
    $tag_value = $xml->$tag;
    if ($name == $tag){ $i++;  }
        $name = $tag;   
      echo $tag .' '.$tag_value[$i].'<br />';
    // recursive
      all_tag($xml->$tag->children());
  }
}
all_tag($xml);
?>

Analyze fully XML.
<?php
$xml = simplexml_load_file('file.xml');
foreach($xml as $key0 => $value){
echo "..1..[$key0] => $value";
foreach($value->attributes() as $attributeskey0 => $attributesvalue1){
echo "________[$attributeskey0] = $attributesvalue1";
}
echo '<br />';
////////////////////////////////////////////////
foreach($value as $key => $value2){
echo "....2.....[$key] => $value2";
foreach($value2->attributes() as $attributeskey => $attributesvalue2){
echo "________[$attributeskey] = $attributesvalue2";
}
echo '<br />';
////////////////////////////////////////////////
foreach($value2 as $key2 => $value3){
echo ".........3..........[$key2] => $value3";
foreach($value3->attributes() as $attributeskey2 => $attributesvalue3){
echo "________[$attributeskey2] = $attributesvalue3";
}
echo '<br />';
////////////////////////////////////////////////
foreach($value3 as $key3 => $value4){
echo "...................4....................[$key3] => $value4";
foreach($value4->attributes() as $attributeskey3 => $attributesvalue4){
echo "________[$attributeskey3] = $attributesvalue4";
}
echo '<br />';
////////////////////////////////////////////////
foreach($value4 as $key4 => $value5){
echo ".....................5......................[$key4] => $value5";
foreach($value5->attributes() as $attributeskey4 => $attributesvalue5){
echo "________[$attributeskey4] = $attributesvalue5";
}
echo '<br />';
////////////////////////////////////////////////
foreach($value5 as $key5 => $value6){
echo "......................6.......................[$key5] => $value6";
foreach($value6->attributes() as $attributeskey5 => $attributesvalue6){
echo "________[$attributeskey5] = $attributesvalue6";
}
echo '<br />';
}}}}}
echo '<br />';
}
?>

If the property of an object is empty the array is not created. Here is a version object2array that transfers properly.
<?php
function object2array($object)
{
  $return = NULL;
    
  if(is_array($object))
  {
    foreach($object as $key => $value)
      $return[$key] = object2array($value);
  } 
  else 
  {
    $var = get_object_vars($object);
      
    if($var) 
    {
      foreach($var as $key => $value)
        $return[$key] = ($key && !$value) ? NULL : object2array($value);
    } 
    else return $object;
  }
  return $return;
}
?>

Micro$oft Word uses non-standard characters and they create problems in using simplexml_load_file.
Many systems include non-standard Word character in their implementation of ISO-8859-1. So an XML document containing that characters can appear well-formed (i.e.) to many browsers. But if you try to load this kind of documents with simplexml_load_file you'll have a little bunch of troubles..
I believe that this is exactly the same question discussed in htmlentites. Following notes to htmlentitles are interesting here too (given in the reverse order, to grant the history):
http://it.php.net/manual/en/function.htmlentities.php#26379
http://it.php.net/manual/en/function.htmlentities.php#41152
http://it.php.net/manual/en/function.htmlentities.php#42126
http://it.php.net/manual/en/function.htmlentities.php#42511

for nested and same name values i'v made up this little bit for getting and displaying multiable values from google's geocode when a exact match is not found it returns all close matches in the following format(this is an abriged version of there output)
<Response>
 <Placemark id="1">
  <address> New York 24, NY, USA</address>
  <AddressDetails>
   ..................
  </AddressDetails>
  <Point>
   <coordinates>-73.5850086,40.7207442,0</coordinates>
  </Point>
 </Placemark>
 <Placemark id="2">
  <address>New York 27, NY, USA</address>
  <AddressDetails>
   ...................
  </AddressDetails>
  <Point>
   <coordinates>-72.8987835,40.8003588,0</coordinates>
  </Point>
 </Placemark>
 <Placemark id="3">
  <address>Cedar Place School, 20 Cedar Pl, Yonkers, NY 10705, USA</address>
  <AddressDetails>
   ..................
  </AddressDetails>
  <Point>
   <coordinates>-73.8966320,40.9256520,0</coordinates>
  </Point>
 </Placemark>
</Response>
<?php
// get and breakdown the results then store them in $var's
$Address = "99999 parkplace, new york, NY";
$urladdress = urlencode($Address);
$Base_url = "http://maps.google.com/maps/geo?q=";
$urlParts = "&output=xml";
$urlrequest = $Base_url . $urladdress . $urlParts;
$xml = simplexml_load_file($urlrequest);
$num = "0";
foreach ($xml->Response->Placemark as $value){ 
  $num++;
  $GeoFindAdd{$num} = $value->address;
  $GeoFindCords{$num} = $value->Point->coordinates;
} 
// a simple display for the results 
echo "Found ",$num," Possable Geo Data Sets <br>";
$CountNumResults = "0";
for ( ; $num > 0; $num--){
  $CountNumResults++;
  echo $countnum,"<br> Address = ",$GeoFindAdd{$num},"<br> Coordinates = ",$GeoFindCords{$num},"<br>";
}
echo "END";
?>

Sorry there's a mistake in the previous function :
<?php
  function &getXMLnode($object, $param) {
    foreach($object as $key => $value) {
      if(isset($object->$key->$param)) {
        return $object->$key->$param;
      }
      if(is_object($object->$key)&&!empty($object->$key)) {
        $new_obj = $object->$key;
        // Must use getXMLnode function there (recursive)
        $ret = getXMLnode($new_obj, $param);  
      }
    }
    if($ret) return (string) $ret;
    return false;
  }
?>

If you need to parse the data from SimpleXML into a session variable remember to define the data as a string first.
If you don't you will get warnings of "Node no longer exists" pointing to your session_start() function.
This will work:
<?php
  $new_version = simplexml_load_file('http://example.com/version.xml');
  $_SESSION['current_version'] = (string)$new_version->version;
?>