The SimpleXMLIterator class
(PHP 5 >= 5.1.3, PHP 7)
简介
The SimpleXMLIterator provides recursive iteration over all nodes of a SimpleXMLElement object.
类摘要
$data
[, int $options
= 0 [, bool $data_is_url
= FALSE
[, string $ns
= "" [, bool $is_prefix
= FALSE
]]]] )$name
[, string $value
[, string $namespace
]] ) : void$name
[, string $value
[, string $namespace
]] ) : SimpleXMLElement$ns
= NULL
[, bool $is_prefix
= FALSE
]] ) : SimpleXMLElement$recursive
= FALSE
[, bool $from_root
= TRUE
]] ) : array}
属性/方法 列表
- SimpleXMLIterator::current — Returns the current element
- SimpleXMLIterator::getChildren — Returns the sub-elements of the current element
- SimpleXMLIterator::hasChildren — Checks whether the current element has sub elements
- SimpleXMLIterator::key — Return current key
- SimpleXMLIterator::next — Move to next element
- SimpleXMLIterator::rewind — Rewind to the first element
- SimpleXMLIterator::valid — Check whether the current element is valid
用户贡献的笔记
The documentation is a bit sparse for SimpleXmlIterator. Here is an example showing the use of its methods. xml2Array and sxiToArray work together to convert an XML document to an associative array structure.
The contents of cats.xml:
======================================
<cats>
<cat>
<name>Jack</name>
<age>2</age>
<color>grey</color>
<color>white</color>
</cat>
<cat>
<name>Maxwell</name>
<age>12</age>
<color>orange</color>
<color>black</color>
</cat>
</cats>
======================================
<?php
function xml2array($fname){
$sxi = new SimpleXmlIterator($fname, null, true);
return sxiToArray($sxi);
}
function
sxiToArray($sxi){
$a = array();
for( $sxi->rewind(); $sxi->valid(); $sxi->next() ) {
if(!array_key_exists($sxi->key(), $a)){
$a[$sxi->key()] = array();
}
if($sxi->hasChildren()){
$a[$sxi->key()][] = sxiToArray($sxi->current());
}
else{
$a[$sxi->key()][] = strval($sxi->current());
}
}
return $a;
}
// Read cats.xml and print the results:
$catArray = xml2array('cats.xml');
print_r($catArray);
?>
Results (reformatted a bit for compactness and clarity):
======================================
Array(
[cat] => Array(
[0] => Array(
[name] => Array( [0] => Jack )
[age] => Array( [0] => 2 )
[color] => Array( [0] => grey,
[1] => white )
)
[1] => Array(
[name] => Array( [0] => Maxwell )
[age] => Array( [0] => 12 )
[color] => Array( [0] => orange
[1] => black )
)
)
)
Most of the time we need to convert the XML to array or JSON , but now I have to completed the requirement of converting XML to XPath which make our template easily geting the data from XML data source due to the Xpath mapping .Here is the function:
<?php
function sxiToXpath($sxi, $key = null, &$tmp = null)
{
$keys_arr = array();
//get the keys count array
for ($sxi->rewind(); $sxi->valid(); $sxi->next())
{
$sk = $sxi->key();
if (array_key_exists($sk, $keys_arr))
{
$keys_arr[$sk]+=1;
$keys_arr[$sk] = $keys_arr[$sk];
}
else
{
$keys_arr[$sk] = 1;
}
}
//create the xpath
for ($sxi->rewind(); $sxi->valid(); $sxi->next())
{
$sk = $sxi->key();
if (!isset($$sk))
{
$$sk = 1;
}
if ($keys_arr[$sk] >= 1)
{
$spk = $sk . '[' . $$sk . ']';
$keys_arr[$sk] = $keys_arr[$sk] - 1;
$$sk++;
}
else
{
$spk = $sk;
}
$kp = $key ? $key . '/' . $spk : '/' . $sxi->getName() . '/' . $spk;
if ($sxi->hasChildren())
{
sxiToXpath($sxi->getChildren(), $kp, $tmp);
}
else
{
$tmp[$kp] = strval($sxi->current());
}
$at = $sxi->current()->attributes();
if ($at)
{
$tmp_kp = $kp;
foreach ($at as $k => $v)
{
$kp .= '/@' . $k;
$tmp[$kp] = $v;
$kp = $tmp_kp;
}
}
}
return $tmp;
}
function
xmlToXpath($xml)
{
$sxi = new SimpleXmlIterator($xml);
return sxiToXpath($sxi);
}
/**
* How to use the function
*/
$xml = <<<EOT
<?xml version="1.0" encoding="utf8" ?>
<data>
<item ID="30001">
<Company>Navarro Corp.</Company>
</item>
<item ID="30002" IDd="30002">
<Company>Performant Systems</Company>
</item>
<item ID="30003">
<Company id='id_test'><g id='id_g'>glove</g></Company>
</item>
<item>
</item>
</data>
EOT;
$rs = xmlToXpath($xml);
print_r($rs);
/**
* the results may lkie this:
Array
(
[/data/item[1]/Company[1]] => Navarro Corp.
[/data/item[1]/@ID] => SimpleXMLIterator Object
(
[0] => 30001
)
[/data/item[2]/Company[1]] => Performant Systems
[/data/item[2]/@ID] => SimpleXMLIterator Object
(
[0] => 30002
)
[/data/item[2]/@IDd] => SimpleXMLIterator Object
(
[0] => 30002
)
[/data/item[3]/Company[1]/g[1]] => glove
[/data/item[3]/Company[1]/g[1]/@id] => SimpleXMLIterator Object
(
[0] => id_g
)
[/data/item[3]/Company[1]/@id] => SimpleXMLIterator Object
(
[0] => id_test
)
[/data/item[3]/@ID] => SimpleXMLIterator Object
(
[0] => 30003
)
[/data/item[4]] =>
)
*/
echo "Total:" . count($rs);
echo
"<hr>";
/* You can check the xpath result like this */
$xml = new SimpleXMLElement($xml);
foreach ($rs as $k => $v)
{
echo "Xpath:" . $k . " Value:" . $v . " ";
var_dump($xml->xpath($k));
echo "<br>";
}
I filled my database from an XML file about 1260 Kb.
I made my process less than a second. Simply by using SimpleXML.
I give you a little example of the usage to fill a database.
Given the table universe.
With 4 columns Coords, Planet_Name, Player_id, Moon_Size.
Now You have a XML file named universe.xml with this kind of data.
I enclose the data within php tags but it's a file :p
<?php
$xml = <<<EOT
<?xml version="1.0" encoding="UTF-8"?>
<universe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" -
xsi:noNamespaceSchemaLocation="http://s127-fr.ogame.gameforge.com/api/xsd/universe.xsd" -
timestamp="1405413350" serverId="fr127">
<planet id="1" player="1" name="Arakis" coords="1:1:2">
<moon id="2" name="Mond" size="4998"/>
</planet>
<planet id="33620176" player="100000" name="GameAdmin" coords="1:1:3"/>
<planet id="33620179" player="100003" name="Heimatplanet" coords="1:1:1"/>
<planet id="33620186" player="100004" name="OGame Team" coords="6:250:1"/>
<planet id="33620242" player="100058" name="KnS" coords="9:1:6">
<moon id="33668391" name="Lune" size="8831"/>
</planet>
</universe>
EOT;
?>
Now how to bring these data in my 4 columns table :
<?php
$newfname = $path."Universe.XML";
$mydata = new SimpleXmlIterator($newfname, 0, true);
$myquery = "INSERT INTO `".$tablename."` (`coords`,`planet_name`, `player_id`, `moon_size`) VALUES ";
for ($mydata->rewind();$mydata->valid();$mydata->next()) {
$myquery.= " ('".$mydata->current()->attributes()['coords']
_."','".utf8_decode($mydata->current()->attributes()['name'])
_."','".utf8_decode($mydata->current()->attributes()['player'])
_."','";
if ($mydata->haschildren()) {
$myquery.= $mydate->current()->children()->attributes()['size']."'),";
} else {
$myquery.= "'),";
}
}
$myquery = rtrim($myquery, ",");
$datatosql = mysql_query($myquery);
?>
I think it's worth mentioning that you need to call the rewind() method on the SimpleXMLIterator object immediately after initialization before you can start doing any other operations on the object. An example:
<?php
$xml = new SimpleXMLIterator('file.xml', null, true);
// $x here will be set to null because the rewind() method has not been called
$x = $xml->current();
$xml->rewind();
// $x here will be set to the first element
$x = $xml->current();
?>
Function to extract SimpleXMLElement data to array.
function extract($sxe = null) {
if (!$sxe instanceOf SimpleXMLElement)
return array();
$extract = array();
foreach ($sxe->children() as $key => $value) {
if (array_key_exists($key, $extract)) {
if (!isset($extract[$key][0])) {
$tmp_extract = $extract[$key];
$extract[$key] = array();
$extract[$key][0] = $tmp_extract;
} else
$extract[$key] = (array) $extract[$key];
}
if ($value->count()) {
if (isset($extract[$key]) && is_array($extract[$key]))
$extract[$key][] = $this->extract($value);
else
$extract[$key] = $this->extract($value);
} else {
if (isset($extract[$key]) && is_array($extract[$key]))
$extract[$key][] = empty(strval($value)) ? null : strval($value);
else
$extract[$key] = empty(strval($value)) ? null : strval($value);
}
}
return $extract;
}
Here's a simple function to convert an XML string to an array -
<?php
// PHP5.3 and above only
function parse($str) {
$f = function($iter) {
foreach($iter as $key=>$val)
$arr[$key][] = ($iter->hasChildren())?
call_user_func (__FUNCTION__, $val)
: strval($val);
return $arr;
};
return $f(new SimpleXmlIterator($str, null));
}
?>
PHP 5.2 and below do not have anonymous functions.
But you can create a helper function to achieve the same thing -
<?php
function parse($str) {
return parseHelper(new SimpleXmlIterator($str, null));
}
function parseHelper($iter) {
foreach($iter as $key=>$val)
$arr[$key][] = ($iter->hasChildren())?
call_user_func (__FUNCTION__, $val)
: strval($val);
return $arr;
}
?>
Using it is straightforward enough -
<?php
$xml
= '
<movies>
<movie>abcd</movie>
<movie>efgh</movie>
<movie>hijk</movie>
</movies>';
var_dump(parse($xml));
?>
This will output -
array
'movie' =>
array
0 => string 'abcd' (length=4)
1 => string 'efgh' (length=4)
2 => string 'hijk' (length=4)