Fixing quote error in invalid XML

A remote service generates invalid XML with attribute values without quotation marks. Example:

<abc invalid=105 valid="105">

In PHP, how can I patch up such 开发者_如何转开发errors in the output? Just passing it to SimpleXML results in an error.

Thanks.

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You are looking for tidy:

$input = '<abc invalid=105 valid="105">';
$tidy = new tidy();
$config = array('output-xml' => true);
$cleanXML = $tidy->repairString($input, $config);