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
韦伦·弗林解决方案的2020版。
const SI_SYMBOLS = ["", "k", "M", "G", "T", "P", "E"];
const abbreviateNumber = (number, minDigits, maxDigits) => {
if (number === 0) return number;
// determines SI symbol
const tier = Math.floor(Math.log10(Math.abs(number)) / 3);
// get suffix and determine scale
const suffix = SI_SYMBOLS[tier];
const scale = 10 ** (tier * 3);
// scale the number
const scaled = number / scale;
// format number and add suffix
return scaled.toLocaleString(undefined, {
minimumFractionDigits: minDigits,
maximumFractionDigits: maxDigits,
}) + suffix;
};
Tests and examples: const abbreviateNumberFactory = (symbols) => ( (number, minDigits, maxDigits) => { if (number === 0) return number; // determines SI symbol const tier = Math.floor(Math.log10(Math.abs(number)) / 3); // get suffix and determine scale const suffix = symbols[tier]; const scale = 10 ** (tier * 3); // scale the number const scaled = number / scale; // format number and add suffix return scaled.toLocaleString(undefined, { minimumFractionDigits: minDigits, maximumFractionDigits: maxDigits, }) + suffix; } ); const SI_SYMBOLS = ["", "k", "M", "G", "T", "P", "E"]; const SHORT_SYMBOLS = ["", "K", "M", "B", "T", "Q"]; const LONG_SYMBOLS = ["", " thousand", " million", " billion", " trillion", " quadrillion"]; const abbreviateNumberSI = abbreviateNumberFactory(SI_SYMBOLS); const abbreviateNumberShort = abbreviateNumberFactory(SHORT_SYMBOLS); const abbreviateNumberLong = abbreviateNumberFactory(LONG_SYMBOLS); const tests = [1e5, -9e7, [1009999.999, 2], [245345235.34513, 1, 1], [-72773144123, 3] ]; const functions = { abbreviateNumberSI, abbreviateNumberShort, abbreviateNumberLong, }; tests.forEach((test) => { const testValue = Array.isArray(test) ? test : [test]; Object.entries(functions).forEach(([key, func]) => { console.log(`${key}(${testValue.join(', ')}) = ${func(...testValue)}`); }); });
其他回答
/**
* Shorten number to thousands, millions, billions, etc.
* http://en.wikipedia.org/wiki/Metric_prefix
*
* @param {number} num Number to shorten.
* @param {number} [digits=0] The number of digits to appear after the decimal point.
* @returns {string|number}
*
* @example
* // returns '12.5k'
* shortenLargeNumber(12543, 1)
*
* @example
* // returns '-13k'
* shortenLargeNumber(-12567)
*
* @example
* // returns '51M'
* shortenLargeNumber(51000000)
*
* @example
* // returns 651
* shortenLargeNumber(651)
*
* @example
* // returns 0.12345
* shortenLargeNumber(0.12345)
*/
function shortenLargeNumber(num, digits) {
var units = ['k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'],
decimal;
for(var i=units.length-1; i>=0; i--) {
decimal = Math.pow(1000, i+1);
if(num <= -decimal || num >= decimal) {
return +(num / decimal).toFixed(digits) + units[i];
}
}
return num;
}
谢谢@Cos的评论,我删除了Math。round10依赖。
以下是我对韦伦·弗林的回答的看法。这将删除.0并修复当层不是整数时的未定义。
const SI_SYMBOL = ['', 'k', 'M', 'G', 'T', 'P', 'E'];
abbreviateNumber(num) {
const tier = Math.floor(Math.log10(num) / 3) || 0;
let result = '' + num;
// if zero, we don't need a suffix
if (tier > 0) {
// get suffix and determine scale
const suffix = SI_SYMBOL[tier];
const scale = Math.pow(10, tier * 3);
// scale the number
const scaled = num / scale;
// format number and add suffix
result = scaled.toFixed(1).replace('.0', '') + suffix;
}
return result;
}
进一步改进Salman's Answer,因为像nFormatter(9999999,1)这样的情况返回1000K。
function formatNumberWithMetricPrefix(num, digits = 1) {
const si = [
{value: 1e18, symbol: 'E'},
{value: 1e15, symbol: 'P'},
{value: 1e12, symbol: 'T'},
{value: 1e9, symbol: 'G'},
{value: 1e6, symbol: 'M'},
{value: 1e3, symbol: 'k'},
{value: 0, symbol: ''},
];
const rx = /\.0+$|(\.[0-9]*[1-9])0+$/;
function divideNum(divider) {
return (num / (divider || 1)).toFixed(digits);
}
let i = si.findIndex(({value}) => num >= value);
if (+divideNum(si[i].value) >= 1e3 && si[i - 1]) {
i -= 1;
}
const {value, symbol} = si[i];
return divideNum(value).replace(rx, '$1') + symbol;
}
下面是一个使用for的选项:
函数numberFormat(d) For (var e = 0;D >= 1000;e + +) { D /= 1000; } return d.toFixed(3) + [", ' k', ' M', ' G'][e]; } let s = numberFormat(9012345678); console.log(s == '9.012 G');
不满足任何张贴的解决方案,所以这是我的版本:
Supports positive and negative numbers Supports negative exponents Rounds up to next exponent if possible Performs bounds checking (doesn't error out for very large/small numbers) Strips off trailing zeros/spaces Supports a precision parameter function abbreviateNumber(number,digits=2) { var expK = Math.floor(Math.log10(Math.abs(number)) / 3); var scaled = number / Math.pow(1000, expK); if(Math.abs(scaled.toFixed(digits))>=1000) { // Check for rounding to next exponent scaled /= 1000; expK += 1; } var SI_SYMBOLS = "apμm kMGTPE"; var BASE0_OFFSET = SI_SYMBOLS.indexOf(' '); if (expK + BASE0_OFFSET>=SI_SYMBOLS.length) { // Bound check expK = SI_SYMBOLS.length-1 - BASE0_OFFSET; scaled = number / Math.pow(1000, expK); } else if (expK + BASE0_OFFSET < 0) return 0; // Too small return scaled.toFixed(digits).replace(/(\.|(\..*?))0+$/,'$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]) ); }