你可以使用正则表达式从字符串中提取数字:

let string = "xxfdx25y93.34xxd73";
let res = string.replace(/\D/g, "");
console.log(res);

输出:25933473

将它包装成一个普通的JavaScript函数:

function onlyNumbers(text){
    return text.replace(/\D/g, "");
}

如果你想从价格(如$6,694.20)中解析一个数字，可以这样做:

parseFloat('$6,694.20'.replace(/^\D|,+/g, ''))

或者通过函数:

function parsePrice(value) {
  return parseFloat(value.replace(/^\D|,+/g, ''))
}

parsePrice('$6,694.20') // 6694.2

使用正则表达式，如何从字符串中获取数字，例如:

String myString = "my 2 first gifts were made by my 4 brothers";
myString = myString.replaceAll("\\D+", "");
System.out.println("myString: " + myString);

myString的结果是“24”。

您可以在http://ideone.com/iOCf5G上看到此运行代码的示例。

试试下面的:string。替换(/ [^ 0 - 9]/ g,”);这将删除所有非数字字符，在字符串中只留下数字

function retnum(str) { 
    var num = str.replace(/[^0-9]/g, ''); 
    return parseInt(num,10); 
}

console.log(“abca12bc45qw”。替换(/ [^ 0 - 9]/ g, ")); console.log(“# box2”。替换(/ [^ 0 - 9]/ g, "));

对于这个具体的例子，

 var thenum = thestring.replace(/^\D+/g, ''); // Replace all leading non-digits with nothing

一般情况下:

 thenum = "foo3bar5".match(/\d+/)[0] // "3"

这里有一个奖励:正则表达式生成器。

function getre(str, num) { if(str === num) return 'nice try'; var res = [/^\D+/g,/\D+$/g,/^\D+|\D+$/g,/\D+/g,/\D.*/g, /.*\D/g,/^\D+|\D.*$/g,/.*\D(?=\d)|\D+$/g]; for(var i = 0; i < res.length; i++) if(str.replace(res[i], '') === num) return 'num = str.replace(/' + res[i].source + '/g, "")'; return 'no idea'; }; function update() { $ = function(x) { return document.getElementById(x) }; var re = getre($('str').value, $('num').value); $('re').innerHTML = 'Numex speaks: <code>' + re + '</code>'; } <p>Hi, I'm Numex, the Number Extractor Oracle. <p>What is your string? <input id="str" value="42abc"></p> <p>What number do you want to extract? <input id="num" value="42"></p> <p><button onclick="update()">Insert Coin</button></p> <p id="re"></p>

let str = "Total Work Duration: 189.56 Hrs.Present: 23.5 Absent: 2";

/* The provided regex globally matches the character
   "." and a digit from the string */
let numArr = str.match(/[\d\.]+/g)

/* It returns an array [189.56, ., 23.5, 2], and
   uses the filter function to remove the '.' */
numArr = numArr.filter(n => n != '.')
console.log(numArr)