删除html标签得到纯文本可处理嵌套的标签

<?php 
/* 
*@Description:删除HTML标签，得到纯文本。可以处理嵌套的标签 
* 
*/ 
class deleteHtmlTags{ 

private $filename; 

function __construct($filename='C:/AppServ/www/text.txt'){ 
$this->filename = $filename; 
} 

/** 
* 删除html标签，得到纯文本。可以处理嵌套的标签,局限性在于连标签内的属性值都会删除掉 
* @access public 
* @param string $string 要处理的html 
* @return string 
*/ 
public function deletehtmltags(){ 
$content = $this->contentGet(); 
while(strstr($content, '>')){ 
$currentBegin = strpos($content, '<'); 
$currentEnd = strpos($content, '>'); 
$cha = $currentEnd - $currentBegin - 1; 
$tmpStringBegin = @substr($content, 0, $currentBegin); 
// $tmpStringMiddle = @ substr($content, $currentBegin + 1, $cha); 
$tmpStringEnd = @substr($content, $currentEnd + 1, strlen($content)); 
// $content = $tmpStringBegin.$tmpStringMiddle.$tmpStringEnd; 
$content = $tmpStringBegin.$tmpStringEnd; 
} 
return $content; 
} 

private function contentGet(){ 
$fd = fopen($this->filename, 'r'); 
$content = fread($fd, filesize($this->filename)); 
fclose($fd); 
return $content; 
} 
} 

$deleteHtml = new deleteHtmlTags(); 
$content = $deleteHtml->deletehtmltags(); 
echo $content; 
?>