本文实例讲述了html">php html">过滤html标记属性类及其用法。是PHP项目开发中比较常见的实用技巧。分享给大家供大家参考。具体方法如下：
HtmlAttributeFilter.class.php类文件如下：
<?php /** HTML Attribute Filter * Date: 2013-09-22 * Author: fdipzone * ver: 1.0 * * Func: * public strip 过滤属性 * public setAllow 设置允许的属性 * public setException 设置特例 * public setIgnore 设置忽略的标记 * private findElements 搜寻需要处理的元素 * private findAttributes 搜寻属性 * private removeAttributes 移除属性 * private isException 判断是否特例 * private createAttributes 创建属性 * private protect 特殊字符转义 */ class HtmlAttributeFilter{ // class start private $_str = ''; // 源字符串 private $_allow = array(); // 允许保留的属性 例如:array('id','class','title') private $_exception = array(); // 特例 例如:array('a'=>array('href','class'),'span'=>array('class')) private $_ignore = array(); // 忽略过滤的标记 例如:array('span','img') /** 处理HTML,过滤不保留的属性 * @param String $str 源字符串 * @return String */ public function strip($str){ $this->_str = $str; if(is_string($this->_str) && strlen($this->_str)>0){ // 判断字符串 $this->_str = strtolower($this->_str); // 转成小写 $res = $this->findElements(); if(is_string($res)){ return $res; } $nodes = $this->findAttributes($res); $this->removeAttributes($nodes); } return $this->_str; } /** 设置允许的属性 * @param Array $param */ public function setAllow($param=array()){ $this->_allow = $param; } /** 设置特例 * @param Array $param */ public function setException($param=array()){ $this->_exception = $param; } /** 设置忽略的标记 * @param Array $param */ public function setIgnore($param=array()){ $this->_ignore = $param; } /** 搜寻需要处理的元素 */ private function findElements(){ $nodes = array(); preg_match_all("/<([^ !\/\>\n]+)([^>]*)>/i", $this->_str, $elements); foreach($elements[1] as $el_key => $element){ if($elements[2][$el_key]){ $literal = $elements[0][$el_key]; $element_name = $elements[1][$el_key]; $attributes = $elements[2][$el_key]; if(is_array($this->_ignore) && !in_array($element_name, $this->_ignore)){ $nodes[] = array('literal'=>$literal, 'name'=>$element_name, 'attributes'=>$attributes); } } } if(!$nodes[0]){ return $this->_str; }else{ return $nodes; } } /** 搜寻属性 * @param Array $nodes 需要处理的元素 */ private function findAttributes($nodes){ foreach($nodes as &$node){ preg_match_all("/([^ =]+)\s*=\s*[\"|']{0,1}([^\"']*)[\"|']{0,1}/i", $node['attributes'], $attributes); if($attributes[1]){ foreach($attributes[1] as $att_key=>$att){ $literal = $attributes[0][$att_key]; $attribute_name = $attributes[1][$att_key]; $value = $attributes[2][$att_key]; $atts[] = array('literal'=>$literal, 'name'=>$attribute_name, 'value'=>$value); } }else{ $node['attributes'] = null; } $node['attributes'] = $atts; unset($atts); } return $nodes; } /** 移除属性 * @param Array $nodes 需要处理的元素 */ private function removeAttributes($nodes){ foreach($nodes as $node){ $node_name = $node['name']; $new_attributes = ''; if(is_array($node['attributes'])){ foreach($node['attributes'] as $attribute){ if((is_array($this->_allow) && in_array($attribute['name'], $this->_allow)) || $this->isException($node_name, $attribute['name'], $this->_exception)){ $new_attributes = $this->createAttributes($new_attributes, $attribute['name'], $attribute['value']); } } } $replacement = ($new_attributes) ? "<$node_name $new_attributes>" : "<$node_name>"; $this->_str = preg_replace('https://www.jb51.net/'.$this->protect($node['literal']).'https://www.jb51.net/', $replacement, $this->_str); } } /** 判断是否特例 * @param String $element_name 元素名 * @param String $attribute_name 属性名 * @param Array $exceptions 允许的特例 * @return boolean */ private function isException($element_name, $attribute_name, $exceptions){ if(array_key_exists($element_name, $this->_exception)){ if(in_array($attribute_name, $this->_exception[$element_name])){ return true; } } return false; } /** 创建属性 * @param String $new_attributes * @param String $name * @param String $value * @return String */ private function createAttributes($new_attributes, $name, $value){ if($new_attributes){ $new_attributes .= " "; } $new_attributes .= "$name=\"$value\""; return $new_attributes; } /** 特殊字符转义 * @param String $str 源字符串 * @return String */ private function protect($str){ $conversions = array( "^" => "\^", "[" => "\[", "." => "\.", "$" => "\$", "{" => "\{", "*" => "\*", "(" => "\(", "\\" => "\\\\", "https://www.jb51.net/" => "\/", "+" => "\+", ")" => "\)", "|" => "\|", "?" => "\?", "<" => "\<", ">" => "\>" ); return strtr($str, $conversions); } } // class end ?>
demo示例代码如下：