php过滤html标签截取部分内容

<?php$str = '<span>fdsfsdf</span><a href="#">href</a>';
echo htmlspecialchars($str).'<Br>';
echo strip_tags($str);?>用strip_tags能把Html标签都去掉，然后调用truncate函数
$array[$row['content_id']]['content_title']=truncate(strip_tags($row['content_title']),21);
function truncate($string,$length,$append = true){$string = trim($string);$strlength = strlen($string);if ($length == 0 || $length >= $strlength){return $string;}elseif ($length < 0){$length = $strlength + $length;if ($length < 0){$length = $strlength;}}if (function_exists('mb_substr')){$newstr = mb_substr($string, 0, $length,"UTF-8");}elseif (function_exists('iconv_substr')){$newstr = iconv_substr($string, 0, $length,"UTF-8");}else{for($i=0;$i<$length;$i++){$tempstring=substr($string,0,1);if(ord($tempstring)>127){$i++;if($i<$length){$newstring[]=substr($string,0,3);$string=substr($string,3);}}else{$newstring[]=substr($string,0,1);$string=substr($string,1);}}$newstr =join($newstring);}if ($append && $string != $newstr){$newstr .= '...';}return $newstr;
}