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
/*including negative values*/
function nFormatter(num) {
let neg = false;
if(num < 0){
num = num * -1;
neg = true;
}
if (num >= 1000000000) {
if(neg){
return -1 * (num / 1000000000).toFixed(1).replace(/\.0$/, '') + 'G';
}
return (num / 1000000000).toFixed(1).replace(/\.0$/, '') + 'G';
}
if (num >= 1000000) {
if(neg){
return -1 * (num / 1000000).toFixed(1).replace(/\.0$/, '') + 'M';
}
return (num / 1000000).toFixed(1).replace(/\.0$/, '') + 'M';
}
if (num >= 1000) {
if(neg){
return -1 * (num / 1000).toFixed(1).replace(/\.0$/, '') + 'K';
}
return (num / 1000).toFixed(1).replace(/\.0$/, '') + 'K';
}
return num;
}
其他回答
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);
下面是一个使用for的选项:
函数numberFormat(d) For (var e = 0;D >= 1000;e + +) { D /= 1000; } return d.toFixed(3) + [", ' k', ' M', ' G'][e]; } let s = numberFormat(9012345678); console.log(s == '9.012 G');
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
通过消除@martin-sznapka解决方案中的循环,您将减少40%的执行时间。
function formatNum(num,digits) {
let units = ['k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'];
let floor = Math.floor(Math.abs(num).toString().length / 3);
let value=+(num / Math.pow(1000, floor))
return value.toFixed(value > 1?digits:2) + units[floor - 1];
}
速度测试(200000随机样本)从这个线程不同的解决方案
Execution time: formatNum 418 ms
Execution time: kFormatter 438 ms it just use "k" no "M".."T"
Execution time: beautify 593 ms doesnt support - negatives
Execution time: shortenLargeNumber 682 ms
Execution time: Intl.NumberFormat 13197ms
一个更普遍的版本:
function nFormatter(num, digits) { const lookup = [ { value: 1, symbol: "" }, { value: 1e3, symbol: "k" }, { value: 1e6, symbol: "M" }, { value: 1e9, symbol: "G" }, { value: 1e12, symbol: "T" }, { value: 1e15, symbol: "P" }, { value: 1e18, symbol: "E" } ]; const rx = /\.0+$|(\.[0-9]*[1-9])0+$/; var item = lookup.slice().reverse().find(function(item) { return num >= item.value; }); return item ? (num / item.value).toFixed(digits).replace(rx, "$1") + item.symbol : "0"; } /* * Tests */ const tests = [ { num: 0, digits: 1 }, { num: 12, digits: 1 }, { num: 1234, digits: 1 }, { num: 100000000, digits: 1 }, { num: 299792458, digits: 1 }, { num: 759878, digits: 1 }, { num: 759878, digits: 0 }, { num: 123, digits: 1 }, { num: 123.456, digits: 1 }, { num: 123.456, digits: 2 }, { num: 123.456, digits: 4 } ]; tests.forEach(function(test) { console.log("nFormatter(" + test.num + ", " + test.digits + ") = " + nFormatter(test.num, test.digits)); });