具体方法如下：
HtmlAttributeFilter.class.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 |
/** 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>"; $this->_str = preg_replace('/'.$this->protect($node['literal']).'/', $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( "^" => "\^", "[" => "\[", "." => "\.", "$" => "\$", "{" => "\{", "*" => "\*", "(" => "\(", "\\" => "\\\\", "/" => "\/", "+" => "\+", ")" => "\)", "|" => "\|", "?" => "\?", " "\ ">" => "\>" ); return strtr($str, $conversions); } } // class end ?> |
demo示例代码如下：
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 |
require('HtmlAttributeFilter.class. $str = ' ';$obj = new HtmlAttributeFilter(); // 允许id属性 $obj->setAllow(array('id')); $obj->setException(array( 'a' => array('href'), // a 标签允许有 href属性特例 'ul' => array('class') // ul 标签允许有 class属性特例 )); // img 标签忽略,不过滤任何属性 $obj->setIgnore(array('img')); echo 'source str: echo htmlspecialchars($str).' echo 'filter str: echo htmlspecialchars($obj->strip($str)); ?> |