php 正则表达式含意

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//取消HTML代码<br />
function shtmlspecialchars($string) {<br />
	if(is_array($string))	{<br />
		foreach($string as $key => $val) {<br />
			$string[$key] = shtmlspecialchars($val);<br />
		}<br />
	} else{<br />
		$string = preg_replace('/&((#(\d{3,5}<br><font color='#FF8000'>------解决方案--------------------</font><br>x[a-fA-F0-9]{4})<br><font color='#FF8000'>------解决方案--------------------</font><br>[a-zA-Z][a-z0-9]{1,5});)/', '&\\1',<br />
			str_replace(array('&', '"', '<', '>','\''), array('&', '"', '<', '>','&#039;'), $string));<br />
	}<br />
	return $string;<br />
}<br />
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