The basic procedure is
- cast a
SimpleXMLElement into an array
- write a comparison function that accepts two
SimpleXMLElement arguments
- sort the array with the comparison function using
usort()
I can only guess at your original XML structure, but I think it looks something like this:
$xml = <<<EOT
<root>
<text>
<body>
<div>
<bibl>
<author>A</author>
<title>A</title>
<date>1</date>
</bibl>
</div>
<div>
<bibl>
<author>B</author>
<title>B</title>
<date>2</date>
</bibl>
</div>
<div>
<bibl>
<author>D</author>
<title>D</title>
<date>4</date>
</bibl>
</div>
<div>
<bibl>
<author>C</author>
<title>C</title>
<date>3</date>
</bibl>
</div>
</body>
</text>
</root>
EOT;
$xmldoc = new SimpleXMLElement($xml);
Step 1: Cast to array. Note that your $divArray is not actually an array!
$divSXE = $xmldoc->text->body->children(); // is a SimpleXMLElement, not an array!
// print_r($divSXE);
$divArray = array();
foreach($divSXE->div as $d) {
$divArray[] = $d;
}
// print_r($divArray);
Step 2: write a comparison function. Since the array is a list of SimpleXMLElements, the comparison function must accept SimpleXMLElement arguments. SimpleXMLElements need explicit casting to get string or integer values.
function author_cmp($a, $b) {
$va = (string) $a->bibl->author;
$vb = (string) $b->bibl->author;
if ($va===$vb) {
return 0;
}
return ($va<$vb) ? -1 : 1;
}
Step 3: Sort the array with usort()
usort($divArray, 'author_cmp');
print_r($divArray);
