var str = "ff ff f f a de def";
str = str.replace(/f/g,'');
alert(str);

HTTP://jsfiddle.net/ANHR9/

我的实践,非常自我解释

function replaceAll(string, token, newtoken) {
    if(token!=newtoken)
    while(string.indexOf(token) > -1) {
        string = string.replace(token, newtoken);
    }
    return string;
}

function replaceAll(str, find, replace) {
  var i = str.indexOf(find);
  if (i > -1){
    str = str.replace(find, replace); 
    i = i + replace.length;
    var st2 = str.substring(i);
    if(st2.indexOf(find) > -1){
      str = str.substring(0,i) + replaceAll(st2, find, replace);
    }       
  }
  return str;
}

我喜欢这个方法(看起来有点干净):

text = text.replace(new RegExp("cat","g"), "dog"); 

可以用常见的表达方式实现这一点,有几种可以帮助某人:

var word = "this,\\ .is*a*test,    '.and? / only /     'a \ test?";
var stri = "This      is    a test         and only a        test";

取代所有非阿尔法字符,

console.log(word.replace(/([^a-z])/g,' ').replace(/ +/g, ' '));
Result: [this is a test and only a test]

用一个空间替换多个连续空间,

console.log(stri.replace(/  +/g,' '));
Result: [This is a test and only a test]

取代所有 * 字符,

console.log(word.replace(/\*/g,''));
Result: [this,\ .isatest,    '.and? / only /     'a  test?]

取代问题标志(?)

console.log(word.replace(/\?/g,'#'));
Result: [this,\ .is*a*test,    '.and# / only /     'a  test#]

取代引用标志,

console.log(word.replace(/'/g,'#'));
Result: [this,\ .is*a*test,    #.and? / only /     #a  test?]

要取代所有“字符”,

console.log(word.replace(/,/g,''));
Result: [this\ .is*a*test    '.and? / only /     'a  test?]

替换一个特定的词,

console.log(word.replace(/test/g,''));
Result: [this,\ .is*a*,    '.and? / only /     'a  ?]

取代Backslash。

console.log(word.replace(/\\/g,''));
Result: [this, .is*a*test,    '.and? / only /     'a  test?]

以替代前滑,

console.log(word.replace(/\//g,''));
Result: [this,\ .is*a*test,    '.and?  only      'a  test?]

替换所有空间,

console.log(word.replace(/ /g,'#'));
Result: [this,\#.is*a*test,####'.and?#/#only#/#####'a##test?]

替换点,

console.log(word.replace(/\./g,'#'));
Result: [this,\ #is*a*test,    '#and? / only /     'a  test?]

截至 2020 年 8 月:现代浏览器支持由 ECMAScript 2021 语言规格定义的 String.replaceAll() 方法。

对于老/古老的浏览器:

function escapeRegExp(string) {
  return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
}

function replaceAll(str, find, replace) {
  return str.replace(new RegExp(escapeRegExp(find), 'g'), replace);
}

这就是这个答案的进化方式:

str = str.replace(/abc/g, '');

回复评论“如果“ABC”被转换为变量,会发生什么?”:

var find = 'abc';
var re = new RegExp(find, 'g');

str = str.replace(re, '');

作为回应 Click Upvote 的评论,您可以更简化:

function replaceAll(str, find, replace) {
  return str.replace(new RegExp(find, 'g'), replace);
}

注意: 常规表达式包含特殊(meta)字符,因此,它是危险的盲目通过一个论点在上面的查找函数,而不提前处理它逃避这些字符。

function escapeRegExp(string) {
  return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
}

因此,为了使上面的替代All() 函数更安全,如果您还包含 EscapeRegExp:

function replaceAll(str, find, replace) {
  return str.replace(new RegExp(escapeRegExp(find), 'g'), replace);
}