如何在 Javascript 保留 space 位置打乱句子？

Question

我 found an script 将打乱字符串：

String.prototype.shuffle = function () {
    var a = this.split(""),
        n = a.length;

    for (var i = n - 1; i > 0; i--) {
        var j = Math.floor(Math.random() * (i + 1));
        var tmp = a[i];
        a[i] = a[j];
        a[j] = tmp;
    }
    return a.join("");
}

使用此脚本，以下单词：

What is the difference in between 'Apache Environment', 'Environment' and 'PHP Variables'?

将随机洗牌到这个词：

ftewE'eim rasent  VhiEAn'oeded ta ' mb one'ennfva'nbcr?n elcttpnP iaWePh'irH rshv ieinena,

但是，我想知道如何保留每个 space:

的原始位置

ftew E' eim rasentVhiE An 'oededt a'mbone 'ennfva'nbcr? nelcttpnPiaWe Ph' irHr shvieinena,

Answer 1

一个选项是创建一个随机字符数组（没有 spaces），然后使用替换非 space 的正则表达式对原始字符串调用 replace在关联索引处的数组中具有项目的字符，在此过程中递增索引：

function shuffleArray(array) {
  for (let i = array.length - 1; i > 0; i--) {
    const j = Math.floor(Math.random() * (i + 1));
    [array[i], array[j]] = [array[j], array[i]];
  }
  return array;
}

String.prototype.shuffle = function () {
  // pass to shuffleArray an array of all non-whitespace characters:
  const randomChars = shuffleArray([...this.replace(/\s+/g, '')]);
  let index = 0;
  // `\S` matches any non-whitespace character:
  return this.replace(/\S/g, () => randomChars[index++]);
}

console.log(
  `What is the difference in between 'Apache Environment', 'Environment' and 'PHP Variables'?`
  .shuffle()
);

还要注意像 String.prototype 这样的改变内置对象通常被认为是非常糟糕的做法，并且会破坏东西；除非你正在填充官方的东西，否则最好使用独立函数：

function shuffleArray(array) {
  for (let i = array.length - 1; i > 0; i--) {
    let j = Math.floor(Math.random() * (i + 1));
    [array[i], array[j]] = [array[j], array[i]];
  }
  return array;
}

function shuffle(str) {
  const randomChars = shuffleArray([...str.replace(/\s+/g, '')]);
  let index = 0;
  return str.replace(/\S/g, () => randomChars[index++]);
}

console.log(shuffle(
  `What is the difference in between 'Apache Environment', 'Environment' and 'PHP Variables'?`
));

Answer 2

如果 a[i] 和 a[j] 是空格，您也可以简单地检查您的函数：

const shuffleMeSoftly = function(str, breaker = ' ') {
  var a = str.split(""),
      n = a.length;

  for (var i = n - 1; i > 0; i--) {
    if (a[i] != breaker) {
      var j = Math.floor(Math.random() * (i + 1));
      if (a[j] != breaker) {
        var tmp = a[i];
        a[i] = a[j];
        a[j] = tmp;
      }
    }
  }
  return a.join("");
}

console.log(shuffleMeSoftly('What is the difference in between \'Apache Environment\', \'Environment\' and \'PHP Variables\'?'))

如何在 Javascript 保留 space 位置打乱句子？

How to scramble a sentence in Javascript preserving space location?

javascript

shuffle

scramble

masking