Question

我尝试检查一个单词（wordToCheck）是否只包含数组中的字母（letters），并且只包含数组中的每个字母（或者更确切地说不是它们的次数）在数组中）因为它实际上在数组内部。

以下是所需功能应返回的示例：

checkIfWordContainsLetters("google", ["a","o","o","g","g","l","e","x"]) === true
checkIfWordContainsLetters("google", ["a","o","g","g","l","e","x"]) === false

如何使此代码有效？

function checkIfWordContainsLetters(wordToCheck, letters) {
    var lettersToString = letters.toString();
    var lettersTrimmed = lettersToString.replace(/,/gi, "?");
    var regEx = new RegExp(lettersTrimmed, "gi");
    if (wordToCheck.match(regEx)!== null) {
        return true;
    }
    else return false;
}

Answer 1

您可以使用此ES6功能：

＆＃13;

function checkIfWordContainsLetters(wordToCheck, letters){
  return !letters.reduce((a, b) => a.replace(b,''), wordToCheck.toLowerCase()).length;
}

console.log(checkIfWordContainsLetters("google", ["a","o","o","g","g","l","e","x"]));
console.log(checkIfWordContainsLetters("google", ["a","o","g","g","l","e","x"]));

＆＃13;

我的想法是浏览 letters 数组中的每个字母，并在给定的 wordToCheck 参数中删除一个（不是更多！）的字母（好吧，不是完全 in 它，但是拿一个缺少那一个字符的副本）。如果在进行这些删除后仍有剩余字符，则返回值为false - true。

当然，如果您使用Internet Explorer，您将无法获得必要的ES6支持。这是与ES5兼容的代码：

＆＃13;

function checkIfWordContainsLetters(wordToCheck, letters){
    return !letters.reduce(function (a, b) {
        return a.replace(b, '');
    }, wordToCheck.toLowerCase()).length;
}

console.log(checkIfWordContainsLetters("google", ["a","o","o","g","g","l","e","x"]));
console.log(checkIfWordContainsLetters("google", ["a","o","g","g","l","e","x"]));

＆＃13;

Answer 2

只要它不是长字符串的最佳解决方案，使用一些聪明的正则表达式肯定更好，它适用于没有空格的短字符串。

function checkIfWordContainsLetters(word, letters){
  word = word.toLowerCase().split('');

  for(var i = 0; i < letters.length; i++) {
    var index = word.indexOf( letters[i].toLowerCase() );
    if( index  !== -1 ) {
      // if word contains that letter, remove it
      word.splice( index , 1 );
      // if words length is 0, return true
      if( !word.length ) return true;
    }
  }
  return false;

}
checkIfWordContainsLetters("google", ["a","o","o","g","g","l","e","x"]); // returns true
checkIfWordContainsLetters("google", ["a","o","g","g","l","e","x"]); // returns false

如何检查字符串是否只包含数组中的字符？

2 个答案: