php中htmlspecialchars和htmlentiti

Certain characters have special significance in HTML, and should be represented by HTML entities if they are to preserve their meanings. This function returns a string with some of these conversions made; the translations made are those most useful for everyday web programming. If you require all HTML character entities to be translated, use htmlentities() instead.

Html entities:&lt &amp…

Html characters：  <>&

使用file_get_contents拿到网页之后，如果直接使用echo 输出，浏览器输出会自动解析，输出仍然为网页。

使用htmlspecialchars转换得到的content，然后获得所有的链接。截取。

截取时候会出现问题，

截取使用htmlspecialchars转换过的内容，截取方式如下：

$word = substr($str,strpos($str,'&gt',5)+4,strpos($str,"&lt",10)-strpos($str,'&gt',5)-4);

function captureKeyArray($url)
{
 $content=file_get_contents($url);
 $pattern="/<a\s+href=.*<\/a>/imsU";
 $match = array();
 preg_match_all($pattern,$content,$match);
 $matchFilter =  array();
 foreach($match[0] as $key=>$val)
    {
   $str= htmlspecialchars($val);
   if(strpos($str,"img"))
   {
   }
   else
   {
       //为什么不能直接过滤掉<,要使用&lt
     $word = substr($str,strpos($str,'&gt',5)+4,strpos($str,"&lt",10)-strpos($str,'&gt',5)-4);
     if($word!="")
     {
     array_push($matchFilter,$word); 
     }
   }
    }
    return $matchFilter;
}