我需要显示一个货币值的格式1K等于一千，或1.1K, 1.2K, 1.9K等，如果它不是一个偶数千，否则如果低于一千，显示正常500,100,250等，使用JavaScript格式化的数字?
当前回答
如果你喜欢，就把功劳归于韦伦·弗林
这比他处理负数和“。0”的情况。
循环和“如果”情况越少，IMO就越好。
function abbreviateNumber(number) {
const SI_POSTFIXES = ["", "k", "M", "G", "T", "P", "E"];
const sign = number < 0 ? '-1' : '';
const absNumber = Math.abs(number);
const tier = Math.log10(absNumber) / 3 | 0;
// if zero, we don't need a prefix
if(tier == 0) return `${absNumber}`;
// get postfix and determine scale
const postfix = SI_POSTFIXES[tier];
const scale = Math.pow(10, tier * 3);
// scale the number
const scaled = absNumber / scale;
const floored = Math.floor(scaled * 10) / 10;
// format number and add postfix as suffix
let str = floored.toFixed(1);
// remove '.0' case
str = (/\.0$/.test(str)) ? str.substr(0, str.length - 2) : str;
return `${sign}${str}${postfix}`;
}
jsFiddle测试用例-> https://jsfiddle.net/qhbrz04o/9/
其他回答
不满足任何张贴的解决方案，所以这是我的版本:
Supports positive and negative numbers Supports negative exponents Rounds up to next exponent if possible Performs bounds checking (doesn't error out for very large/small numbers) Strips off trailing zeros/spaces Supports a precision parameter function abbreviateNumber(number,digits=2) { var expK = Math.floor(Math.log10(Math.abs(number)) / 3); var scaled = number / Math.pow(1000, expK); if(Math.abs(scaled.toFixed(digits))>=1000) { // Check for rounding to next exponent scaled /= 1000; expK += 1; } var SI_SYMBOLS = "apμm kMGTPE"; var BASE0_OFFSET = SI_SYMBOLS.indexOf(' '); if (expK + BASE0_OFFSET>=SI_SYMBOLS.length) { // Bound check expK = SI_SYMBOLS.length-1 - BASE0_OFFSET; scaled = number / Math.pow(1000, expK); } else if (expK + BASE0_OFFSET < 0) return 0; // Too small return scaled.toFixed(digits).replace(/(\.|(\..*?))0+$/,'$2') + SI_SYMBOLS[expK+BASE0_OFFSET].trim(); } ////////////////// const tests = [ [0.0000000000001,2], [0.00000000001,2], [0.000000001,2], [0.000001,2], [0.001,2], [0.0016,2], [-0.0016,2], [0.01,2], [1,2], [999.99,2], [999.99,1], [-999.99,1], [999999,2], [999999999999,2], [999999999999999999,2], [99999999999999999999,2], ]; for (var i = 0; i < tests.length; i++) { console.log(abbreviateNumber(tests[i][0], tests[i][1]) ); }
进一步改进Salman's Answer，因为它将nFormatter(33000)返回为33.0K
function nFormatter(num) {
if (num >= 1000000000) {
return (num / 1000000000).toFixed(1).replace(/\.0$/, '') + 'G';
}
if (num >= 1000000) {
return (num / 1000000).toFixed(1).replace(/\.0$/, '') + 'M';
}
if (num >= 1000) {
return (num / 1000).toFixed(1).replace(/\.0$/, '') + 'K';
}
return num;
}
now nFormatter(33000) = 33K
ES2020在Intl中增加了对此的支持。使用如下表示法:
let formatter = Intl。NumberFormat('en'，{符号:'紧凑'}); //示例1 让million = formatter.format(1e6); //示例2 Let billion = formatter.format(1e9); / /打印 console.log(million == '1M'， billion == '1B');
注意如上所示，第二个示例生成1B而不是1G。 NumberFormat规格:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat/NumberFormat https://tc39.es/ecma402#numberformat-objects
注意，目前并不是所有的浏览器都支持ES2020，所以你可能需要这个 Polyfill: https://formatjs.io/docs/polyfills/intl-numberformat
这个函数可以将巨大的数字(正数和负数)转换为读者友好的格式，而不会失去其精度:
function abbrNum(n) { if (!n || (n && typeof n !== 'number')) { return ''; } const ranges = [ { divider: 1e12 , suffix: 't' }, { divider: 1e9 , suffix: 'b' }, { divider: 1e6 , suffix: 'm' }, { divider: 1e3 , suffix: 'k' } ]; const range = ranges.find(r => Math.abs(n) >= r.divider); if (range) { return (n / range.divider).toString() + range.suffix; } return n.toString(); } /* test cases */ let testAry = [99, 1200, -150000, 9000000]; let resultAry = testAry.map(abbrNum); console.log("result array: " + resultAry);
这里有一个简单的解决方案，可以避免所有的if语句(借助Math的力量)。
var SI_SYMBOL = ["", "k", "M", "G", "T", "P", "E"];
function abbreviateNumber(number){
// what tier? (determines SI symbol)
var tier = Math.log10(Math.abs(number)) / 3 | 0;
// if zero, we don't need a suffix
if(tier == 0) return number;
// get suffix and determine scale
var suffix = SI_SYMBOL[tier];
var scale = Math.pow(10, tier * 3);
// scale the number
var scaled = number / scale;
// format number and add suffix
return scaled.toFixed(1) + suffix;
}
奖金模因
SI代表什么?
