我知道我们必须使用正则表达式，但在一次采访中，我被要求不要使用正则表达式。

@slightlytyler帮助我提出了下面的方法。

const testStr = "I LOVE STACKOVERFLOW LOL"; const removeSpaces = str => { Const chars = str.split("); const nextChars = char .reduce( (acc, c) => { If (c === ' ') { const lastChar = acc[acc.]长度- 1]; if (lastChar === ' ') { 返回acc; } } 返回[…acc, c]; }， [], ）; const nextStr = nextchar .join("); 返回nextStr }; console.log (removeSpaces (testStr));

var text = `xxx  df dfvdfv  df    
                     dfv`.split(/[\s,\t,\r,\n]+/).filter(x=>x).join(' ');

结果:

"xxx df dfvdfv df dfv"

我有一个方法，我叫它Derp方法因为没有更好的名字。

while (str.indexOf("  ") !== -1) {
    str = str.replace(/  /g, " ");
}

在JSPerf中运行它会得到一些令人惊讶的结果，它击败了一些更复杂的方法EDIT原始JSPerf链接http://jsperf.com/removing-multiple-spaces/3当时似乎已经死了

这个脚本删除了单词和修饰之间的任何空白(多个空格，制表符，返回值等):

// Trims & replaces any wihtespacing to single space between words
String.prototype.clearExtraSpace = function(){
  var _trimLeft  = /^\s+/,
      _trimRight = /\s+$/,
      _multiple  = /\s+/g;

  return this.replace(_trimLeft, '').replace(_trimRight, '').replace(_multiple, ' ');
};

尝试用一个空格替换多个空格。

<script type="text/javascript">
    var myStr = "The dog      has a long   tail, and it     is RED!";
    alert(myStr);  // Output 'The dog      has a long   tail, and it     is RED!'

    var newStr = myStr.replace(/  +/g, ' ');
    alert(newStr);  // Output 'The dog has a long tail, and it is RED!'
</script>

阅读更多@用单个空格替换多个空格

var string = "The dog      has a long   tail, and it     is RED!";
var replaced = string.replace(/ +/g, " ");

或者如果你也想替换制表符:

var replaced = string.replace(/\s+/g, " ");