Erro DOM - ID 'someAnchor' já definido na Entidade, linha X

Question

Sep 01, 2010, 04:10 AM

Erro DOM - ID 'someAnchor' já definido na Entidade, linha X

Se eu tentar carregar um documento HTML no PHP DOM, recebo um erro ao longo das linhas de:

Error DOMDocument::loadHTML() [domdocument.loadhtml]: ID someAnchor already defined in Entity, line: 9

Não consigo entender o porquê. Aqui está um código que carrega uma string HTML no DOM.

Primeiro sem conter uma marca de âncora e segundo com uma. O segundo documento produz um erro.

Espero que você consiga recortá-lo e colá-lo em um script e executá-lo para ver a mesma saída:

<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);


$stringWithNoAnchor = <<<EOT
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>My document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body >
<h1>Hello</h1>
</body>
</html>
EOT;

$stringWithAnchor = <<<EOT
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>My document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body >
<h1>Hello</h1>
<a name="someAnchor" id="someAnchor"></a>
</body>
</html>
EOT;

class domGrabber
    {
    public $_FileErrorStr = '';

    /**
    *@desc DOM object factory does the work of loading the DOM object
    */
    public function getLoadAsDOMObj($htmlString)
        {
        $this->_FileErrorStr =''; //reset error container
        $xmlDoc = new DOMDocument();
        set_error_handler(array($this, '_FileErrorHandler')); // Warnings and errors are suppressed
        $xmlDoc->loadHTML($htmlString);
        restore_error_handler();
        return $xmlDoc;
        }

    /**
    *@desc public so that it can catch errors from outside this class
    */
    public function _FileErrorHandler($errno, $errstr, $errfile, $errline)
        {
        if ($this->_FileErrorStr === null)
            {
            $this->_FileErrorStr = $errstr;
            }
        else    {
            $this->_FileErrorStr .= (PHP_EOL . $errstr);
            }
        }
    }

$domGrabber = new  domGrabber();
$xmlDoc = $domGrabber->getLoadAsDOMObj($stringWithNoAnchor );

echo 'PHP Version: '. phpversion() .'<br />'."\n";

echo '<pre>';
print $xmlDoc->saveXML();
echo '</pre>'."\n";
if ($domGrabber->_FileErrorStr)
    {
    echo 'Error'. $domGrabber->_FileErrorStr;
    }



$xmlDoc = $domGrabber->getLoadAsDOMObj($stringWithAnchor);
echo '<pre>';
print $xmlDoc->saveXML();
echo '</pre>'."\n";
if ($domGrabber->_FileErrorStr)
    {
    echo 'Error'. $domGrabber->_FileErrorStr;
    }

Recebo o seguinte na minha exibição de código-fonte do Firefox:

PHP Version: 5.2.9<br />
<pre><?xml version="1.0" encoding="iso-8859-1" standalone="yes"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xmlns="http://www.w3.org/1999/xhtml"><head><title>My document</title><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /></head><body>
<h1>Hello</h1>
</body></html>
</pre>
<pre><?xml version="1.0" encoding="iso-8859-1" standalone="yes"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xmlns="http://www.w3.org/1999/xhtml"><head><title>My document</title><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /></head><body>
<h1>Hello</h1>
<a name="someAnchor" id="someAnchor"></a>

</body></html>
</pre>
Error
DOMDocument::loadHTML() [<a href='domdocument.loadhtml'>domdocument.loadhtml</a>]: ID someAnchor already defined in Entity, line: 9

Então, por que o DOM está dizendo que someAnchor já está definido?

Atualizar:

Eu experimentei com ambos

Em vez de usar loadHTML (), usei o método loadXML () - e isso foi corrigidoEm vez de ter id e nome, usei apenas id - Attribute e isso foi corrigido.

Veja o script de comparação aqui para concluir:

<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);


$stringWithNoAnchor = <<<EOT
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>My document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body >
<p>stringWithNoAnchor</p>
</body>
</html>
EOT;

$stringWithAnchor = <<<EOT
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>My document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body >
<p>stringWithAnchor</p>
<a  name="someAnchor" id="someAnchor" ></a>
</body>
</html>
EOT;

$stringWithAnchorButOnlyIdAtt = <<<EOT
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>My document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
</head>
<body >
<p>stringWithAnchorButOnlyIdAtt</p>
<a id="someAnchor"></a>
</body>
</html>
EOT;

class domGrabber
    {
    public $_FileErrorStr = '';
    public $useHTMLMethod = TRUE;

    /**
    *@desc DOM object factory does the work of loading the DOM object
    */
    public function loadDOMObjAndWriteOut($htmlString)
        {
        $this->_FileErrorStr ='';

        $xmlDoc = new DOMDocument();
        set_error_handler(array($this, '_FileErrorHandler')); // Warnings and errors are suppressed


        if ($this->useHTMLMethod)
            {
            $xmlDoc->loadHTML($htmlString);
            }
        else    {
            $xmlDoc->loadXML($htmlString);
            }


        restore_error_handler();

        echo "<h1>";
        echo ($this->useHTMLMethod) ? 'using xmlDoc->loadHTML() ' : 'using $xmlDoc->loadXML()';
        echo "</h1>";
        echo '<pre>';
        print $xmlDoc->saveXML();
        echo '</pre>'."\n";
        if ($this->_FileErrorStr)
            {
            echo 'Error'. $this->_FileErrorStr;
            }
        }

    /**
    *@desc public so that it can catch errors from outside this class
    */
    public function _FileErrorHandler($errno, $errstr, $errfile, $errline)
        {
        if ($this->_FileErrorStr === null)
            {
            $this->_FileErrorStr = $errstr;
            }
        else    {
            $this->_FileErrorStr .= (PHP_EOL . $errstr);
            }
        }
    }

$domGrabber = new  domGrabber();

echo 'PHP Version: '. phpversion() .'<br />'."\n";

$domGrabber->useHTMLMethod = TRUE; //DOM->loadHTML
$domGrabber->loadDOMObjAndWriteOut($stringWithNoAnchor);
$domGrabber->loadDOMObjAndWriteOut($stringWithAnchor );
$domGrabber->loadDOMObjAndWriteOut($stringWithAnchorButOnlyIdAtt);

$domGrabber->useHTMLMethod = FALSE; //use DOM->loadXML
$domGrabber->loadDOMObjAndWriteOut($stringWithNoAnchor);
$domGrabber->loadDOMObjAndWriteOut($stringWithAnchor );
$domGrabber->loadDOMObjAndWriteOut($stringWithAnchorButOnlyIdAtt);