JavaScript通配符匹配单词功能异常排查求助

你好呀！我看了你的代码和问题描述，马上就发现问题出在哪了——你现在的思路是把生成的字母加上星号拼成字符串，然后用includes()去检查字典数组里有没有完全等于这个带星号字符串的单词，但includes()是完全匹配，它只会找和wildGen一模一样的元素，而字典里的单词都是正常的英文单词，根本没有带星号的，所以当然永远返回“Invalid permutation”啦！

比如你说的i、t、a的情况，你生成的wildGen是*i*t*a*，而字典里的是dictionary，includes()只会判断数组里有没有*i*t*a*这个字符串，完全不会把星号当成通配符去匹配单词里的顺序字母。

那该怎么改呢？我们需要实现一个按顺序的通配符匹配逻辑，也就是检查字典里的某个单词是否能按顺序找到你生成的三个字母（中间可以有其他字符）。

给你两种修改方案：

方案一：用正则表达式实现通配符匹配 #

我们可以把生成的三个字母转换成正则表达式，比如把i、t、a转换成/.*i.*t.*a.*/，这样就能匹配任何包含i、t、a按顺序出现的字符串了。修改后的代码如下：

//define dictionary and alphabet
const dictionaryArray = ["alligator", "breadcrumb", "creation", "dictionary", "elephant", "farm", "general"];
const alphabet = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"];

/*implement function to generate a random number. 
In conjunction with alphabet array, this will generate 
random letters */
function Random(maxNumber) {
    return Math.floor(Math.random() * maxNumber);
}

//generate random letters
var genLet1 = alphabet[Random(26)];
var genLet2 = alphabet[Random(26)];
var genLet3 = alphabet[Random(26)];

// 生成正则表达式：匹配任意字符（.*）分隔三个字母的情况
const regexPattern = new RegExp(`.*${genLet1}.*${genLet2}.*${genLet3}.*`);

function checkPermutationValidity() {
  // 检查字典里是否有单词符合正则表达式
  const isValid = dictionaryArray.some(word => regexPattern.test(word));
  if (isValid) {
    console.log("Valid permutation");
  } else {
    console.log("Invalid permutation");
  }
}
checkPermutationValidity();

方案二：手动遍历单词检查顺序 #

如果你不想用正则，也可以手动写一个函数，逐个检查单词里是否按顺序包含三个字母：

//define dictionary and alphabet
const dictionaryArray = ["alligator", "breadcrumb", "creation", "dictionary", "elephant", "farm", "general"];
const alphabet = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"];

/*implement function to generate a random number. 
In conjunction with alphabet array, this will generate 
random letters */
function Random(maxNumber) {
    return Math.floor(Math.random() * maxNumber);
}

//generate random letters
var genLet1 = alphabet[Random(26)];
var genLet2 = alphabet[Random(26)];
var genLet3 = alphabet[Random(26)];

// 手动检查单词是否按顺序包含三个字母
function hasOrderedLetters(word, a, b, c) {
  let indexA = word.indexOf(a);
  if (indexA === -1) return false;
  let indexB = word.indexOf(b, indexA + 1);
  if (indexB === -1) return false;
  let indexC = word.indexOf(c, indexB + 1);
  return indexC !== -1;
}

function checkPermutationValidity() {
  const isValid = dictionaryArray.some(word => hasOrderedLetters(word, genLet1, genLet2, genLet3));
  if (isValid) {
    console.log("Valid permutation");
  } else {
    console.log("Invalid permutation");
  }
}
checkPermutationValidity();

这两种方案都能解决你的问题，比如当生成i、t、a的时候，都会匹配到dictionary，返回“Valid permutation”啦！

备注：内容来源于stack exchange，提问作者Maeve Convery