格式化xml字符串

Question

在PHP类中格式化XML的最佳方法是什么.

$xml = "<element attribute=\"something\">...</element>";

$xml = '<element attribute="something">...</element>';

$xml = '<element attribute=\'something\'>...</element>';

$xml = <<<EOF
<element attribute="something">
</element>
EOF;

我很确定这是最后一个!

Answer 1

使用DOM,您可以做到

$dom = new DOMDocument;
$dom->preserveWhiteSpace = FALSE;
$dom->loadXML('<root><foo><bar>baz</bar></foo></root>');
$dom->formatOutput = TRUE;
echo $dom->saveXML();

给(现场演示)

<?xml version="1.0"?>
<root>
  <foo>
    <bar>baz</bar>
  </foo>
</root>

请参阅DOMDocument::formatOutput和DOMDocument::preserveWhiteSpace属性说明.

Answer 2

这个函数完美地工作,因为你不需要使用任何xml dom库或nething只是将xml生成的字符串传递给它,它将解析并生成带有制表符和换行符的新字符串.

function formatXmlString($xml){
    $xml = preg_replace('/(>)(<)(\/*)/', "$1\n$2$3", $xml);
    $token      = strtok($xml, "\n");
    $result     = '';
    $pad        = 0; 
    $matches    = array();
    while ($token !== false) : 
        if (preg_match('/.+<\/\w[^>]*>$/', $token, $matches)) : 
          $indent=0;
        elseif (preg_match('/^<\/\w/', $token, $matches)) :
          $pad--;
          $indent = 0;
        elseif (preg_match('/^<\w[^>]*[^\/]>.*$/', $token, $matches)) :
          $indent=1;
        else :
          $indent = 0; 
        endif;
        $line    = str_pad($token, strlen($token)+$pad, ' ', STR_PAD_LEFT);
        $result .= $line . "\n";
        $token   = strtok("\n");
        $pad    += $indent;
    endwhile; 
    return $result;
}

Answer 3

//这是使用XMLWriter的示例

$w = new XMLWriter;
$w->openMemory();
$w->setIndent(true);
  $w->startElement('foo');
    $w->startElement('bar');
      $w->writeElement("key", "value");
    $w->endElement();
  $w->endElement();
echo $w->outputMemory();

//输出

<foo> 
 <bar> 
  <key>value</key> 
 </bar> 
</foo>