JavaScript 实现敏感词过滤：DFA算法原理与性能对比

/**
* @description
* 构造敏感词map
* @private
* @returns
*/
private makeSensitiveMap(sensitiveWordList) {
 // 构造根节点
 const result = new Map();
 for (const word of sensitiveWordList) {
  let map = result;
  for (let i = 0; i < word.length; i++) {
   // 依次获取字
   const char = word.charAt(i);
   // 判断是否存在
   if (map.get(char)) {
    // 获取下一层节点
    map = map.get(char);
   } else {
    // 将当前节点设置为非结尾节点
    if (map.get('laster') === true) {
     map.set('laster', false);
    }
    const item = new Map();
    // 新增节点默认为结尾节点
    item.set('laster', true);
    map.set(char, item);
    map = map.get(char);
   }
  }

 }
 return result;
}

/**
* @description
* 检查敏感词是否存在
* @private
* @param {any} txt
* @param {any} index
* @returns
*/
private checkSensitiveWord(sensitiveMap, txt, index) {
 let currentMap = sensitiveMap;
 let flag = false;
 let wordNum = 0;//记录过滤
 let sensitiveWord = ''; //记录过滤出来的敏感词
 for (let i = index; i < txt.length; i++) {
  const word = txt.charAt(i);
  currentMap = currentMap.get(word);
  if (currentMap) {
   wordNum++;
   sensitiveWord += word;
   if (currentMap.get('laster') === true) {
    // 表示已到词的结尾
    flag = true;
    break;
   }
  } else {
   break;
  }
 }
 // 两字成词
 if (wordNum < 2) {
  flag = false;
 }
 return { flag, sensitiveWord };
}
/**
* @description
* 判断文本中是否存在敏感词
* @param {any} txt
* @returns
*/
public filterSensitiveWord(txt, sensitiveMap) {
 let matchResult = { flag: false, sensitiveWord: '' };
 // 过滤掉除了中文、英文、数字之外的
 const txtTrim = txt.replace(/[^\u4e00-\u9fa5\u0030-\u0039\u0061-\u007a\u0041-\u005a]+/g, '');
 for (let i = 0; i < txtTrim.length; i++) {
  matchResult = checkSensitiveWord(sensitiveMap, txtTrim, i);
  if (matchResult.flag) {
   console.log(`sensitiveWord:${matchResult.sensitiveWord}`);
   break;
  }
 }
 return matchResult;
}

// 简单的字符串匹配-indexOf
ensitiveWords.forEach((word) => {
 if (ss.indexOf(word) !== -1) {
  console.log(word)
 }
})