php实现的替换敏感字符串类实例

本文实例讲述了PHP实现的替换敏感字符串类及其用法，在PHP程序开发中有着非常广泛的应用价值。分享给大家供大家参考。具体方法如下：

StrFilter.class.PHP类文件如下：

rush:PHP;"> private $_white_list = array();
private $_black_list = array();
private $_replacement = '*';
private $_LTAG = '[[##';
private $_RTAG = '##]]';

/**

• @param Array $white_list
• @param Array $black_list
• @param String $replacement
  /
  public function __construct($white_list=array(),$black_list=array(),$replacement=''){
  $this->_white_list = $white_list;
  $this->_black_list = $black_list;
  $this->_replacement = $replacement;
  }

/** 替换非法字符

• @param String $content 要替換的字符串

• @return String 替換后的字符串
  */
  public function replace($content){

  if(!isset($content) || $content==''){
  return '';
  }

  // protect white list
  $content = $this->protect_white_list($content);

  // replace black list
  if($this->_black_list){
  foreach($this->_black_list as $val){
  $content = str_replace($val,$this->_replacement,$content);
  }
  }

  // resume white list
  $content = $this->resume_white_list($content);

  return $content;
  }

/** 检查是否含有非法自符

• @param String $content 字符串

• @return boolean
  */
  public function check($content){

  if(!isset($content) || $content==''){
  return true;
  }

  // protect white list
  $content = $this->protect_white_list($content);

  // check
  if($this->_black_list){
  foreach($this->_black_list as $val){
  if(strstr($content,$val)!=''){
  return false;
  }
  }
  }
  return true;
  }

/** 保护白名单

• @param String $content 字符串
• @return String
  */
  private function protect_white_list($content){
  if($this->_white_list){
  foreach($this->_white_list as $key=>$val){
  $content = str_replace($val,$this->_LTAG.$key.$this->_RTAG,$content);
  }
  }
  return $content;
  }

/** 还原白名单

• @param String $content
• @return String
  /
  private function resume_white_list($content){
  if($this->_white_list){
  $content = preg_replace_callback("/[[##(.?)##]].*?/si",array($this,'getval'),$content);
  }
  return $content;
  }

/** 白名单 key还原为value

• @param Array $matches 匹配white_list的key
• @return String white_list val
  */
  private function getval($matches){
  return isset($this->_white_list[$matches[1]])? $this->_white_list[$matches[1]] : ''; // key->val
  }
  } // class end
  ?>

demo示例如下：

rush:PHP;"> require("StrFilter.class.php");

$white = array('屌丝','曹操');
$black = array('屌','操');

$content = "我操,曹操你是屌丝,我屌你啊";

$obj = new StrFilter($white,$black);
echo $obj->replace($content);
?>

完整实例代码点击

希望本文所述对大家PHP程序设计的学习有所帮助。