xml_parse_into_struct

PHP 4, PHP 5, PHP 7, PHP 8

xml_parse_into_struct - Parse XML data into an array structure

Code Examples

Example #1 xml_parse_into_struct example

tag, and then we parse this and print out the structures generated:

Result: Index array Array ( [PARA] => Array ( [0] => 0 [1] => 2 ) [NOTE] => Array ( [0] => 1 ) ) Vals array Array ( [0] => Array ( [tag] => PARA [type] => open [level] => 1 ) [1] => Array ( [tag] => NOTE [type] => complete [level] => 2 [value] => simple note ) [2] => Array ( [tag] => PARA [type] => close [level] => 1 ) )

Edit/Test in Sandbox

PHP Version:

Example #2 parsemoldb.php - parses moldb.xml into an array of molecular objects

And some code to parse the document and generate the appropriate objects:

<?php
class AminoAcid {
    var $name;  // aa name
    var $symbol;    // three letter symbol
    var $code;  // one letter code
    var $type;  // hydrophobic, charged or neutral
    function __construct ($aa) 
    {
        foreach ($aa as $k=>$v)
            $this->$k = $aa[$k];
    }
}
function readDatabase($filename) 
{
    // read the XML database of aminoacids
    $data = file_get_contents($filename);
    $parser = xml_parser_create();
    xml_parser_set_option($parser, XML_OPTION_CASE_FOLDING, 0);
    xml_parser_set_option($parser, XML_OPTION_SKIP_WHITE, 1);
    xml_parse_into_struct($parser, $data, $values, $tags);
    xml_parser_free($parser);
    // loop through the structures
    foreach ($tags as $key=>$val) {
        if ($key == "molecule") {
            $molranges = $val;
            // each contiguous pair of array entries are the 
            // lower and upper range for each molecule definition
            for ($i=0; $i < count($molranges); $i+=2) {
                $offset = $molranges[$i] + 1;
                $len = $molranges[$i + 1] - $offset;
                $tdb[] = parseMol(array_slice($values, $offset, $len));
            }
        } else {
            continue;
        }
    }
    return $tdb;
}
function parseMol($mvalues) 
{
    for ($i=0; $i < count($mvalues); $i++) {
        $mol[$mvalues[$i]["tag"]] = $mvalues[$i]["value"];
    }
    return new AminoAcid($mol);
}
$db = readDatabase("moldb.xml");
echo "** Database of AminoAcid objects:\n";
print_r($db);

Edit/Test in Sandbox

PHP Version:

Example #3 moldb.xml - small database of molecular information

Event-driven parsing (based on the expat library) can get complicated when you have an XML document that is complex. This function does not produce a DOM style object, but it generates structures amenable of being traversed in a tree fashion. Thus, we can create objects representing the data in the XML file easily. Let's consider the following XML file representing a small database of aminoacids information:

Edit/Test in Sandbox

PHP Version:

xml_parse_into_struct

Example #1 xml_parse_into_struct example

Example #2 parsemoldb.php - parses moldb.xml into an array of molecular objects

Example #3 moldb.xml - small database of molecular information

Function xml_parse_into_struct:

XML Parser Functions

Most used PHP functions