我需要以等于1K或1K,1.1K,1.2K,1.9K等的1K格式显示货币值,如果不是偶数,则为1000,否则显示正常的500、100、250等,使用javascript格式化数字?
我需要以等于1K或1K,1.1K,1.2K,1.9K等的1K格式显示货币值,如果不是偶数,则为1000,否则显示正常的500、100、250等,使用javascript格式化数字?
Answers:
听起来这应该适合您:
function kFormatter(num) {
    return Math.abs(num) > 999 ? Math.sign(num)*((Math.abs(num)/1000).toFixed(1)) + 'k' : Math.sign(num)*Math.abs(num)
}
    
console.log(kFormatter(1200)); // 1.2k
console.log(kFormatter(-1200)); // -1.2k
console.log(kFormatter(900)); // 900
console.log(kFormatter(-900)); // -900
$mynumber_output哪里插入它以使用它?例如,说$mynumber_output= 12846,我希望将12846转换为12.8k
                    更通用的版本:
function nFormatter(num, digits) {
  var si = [
    { 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" }
  ];
  var rx = /\.0+$|(\.[0-9]*[1-9])0+$/;
  var i;
  for (i = si.length - 1; i > 0; i--) {
    if (num >= si[i].value) {
      break;
    }
  }
  return (num / si[i].value).toFixed(digits).replace(rx, "$1") + si[i].symbol;
}
/*
 * Tests
 */
var tests = [
  { 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 }
];
var i;
for (i = 0; i < tests.length; i++) {
  console.log("nFormatter(" + tests[i].num + ", " + tests[i].digits + ") = " + nFormatter(tests[i].num, tests[i].digits));
}
if (num >= si[i].value)为if (Math.abs(num) >= si[i].value)
                    .replace(rx, "$1")办?
                    1.0变得1和1.10变得1.1
                    这是一个避免所有if语句(使用的功能Math)的简单解决方案。
var SI_SYMBOL = ["", "k", "M", "G", "T", "P", "E"];
function abbreviateNumber(number){
    // what tier? (determines SI symbol)
    var tier = Math.log10(number) / 3 | 0;
    // if zero, we don't need a suffix
    if(tier == 0) return number;
    // get suffix and determine scale
    var suffix = SI_SYMBOL[tier];
    var scale = Math.pow(10, tier * 3);
    // scale the number
    var scaled = number / scale;
    // format number and add suffix
    return scaled.toFixed(1) + suffix;
}
Math.abs即可为负数添加支持,例如:var tier = Math.log10(Math.abs(number)) / 3 | 0;。
                    进一步改进Salman的答案,因为它将nFormatter(33000)返回为33.0K
function nFormatter(num) {
     if (num >= 1000000000) {
        return (num / 1000000000).toFixed(1).replace(/\.0$/, '') + '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;
}
现在nFormatter(33000)= 33K
/**
 * 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;
}
Thx @Cos发表评论,我删除了Math.round10依赖项。
Math.abs(num) >= decimal。
                    使用Math对象,map对象,for循环,正则表达式等,此线程上的许多答案变得相当复杂。但是这些方法并不能真正提高代码的可读性或性能。直截了当的方法似乎可以提供最佳设计。
const formatCash = n => {
  if (n < 1e3) return n;
  if (n >= 1e3) return +(n / 1e3).toFixed(1) + "K";
};
console.log(formatCash(2500));
const formatCash = n => {
  if (n < 1e3) return n;
  if (n >= 1e3 && n < 1e6) return +(n / 1e3).toFixed(1) + "K";
  if (n >= 1e6 && n < 1e9) return +(n / 1e6).toFixed(1) + "M";
  if (n >= 1e9 && n < 1e12) return +(n / 1e9).toFixed(1) + "B";
  if (n >= 1e12) return +(n / 1e12).toFixed(1) + "T";
};
console.log(formatCash(1235000));
let format;
const number = -1235000;
if (number < 0) {
  format = '-' + formatCash(-1 * number);
} else {
  format = formatCash(number);
}
              '-'  +  formatCash(-1 * number)
                    从他处理负数和“ .0”大小写的更优雅的方法改进了这一点。
循环和“如果”情况越少,IMO越好。
function abbreviateNumber(number) {
    var SI_POSTFIXES = ["", "k", "M", "G", "T", "P", "E"];
    var tier = Math.log10(Math.abs(number)) / 3 | 0;
    if(tier == 0) return number;
    var postfix = SI_POSTFIXES[tier];
    var scale = Math.pow(10, tier * 3);
    var scaled = number / scale;
    var formatted = scaled.toFixed(1) + '';
    if (/\.0$/.test(formatted))
      formatted = formatted.substr(0, formatted.length - 2);
    return formatted + postfix;
}
带有测试用例的jsFiddle-> https://jsfiddle.net/xyug4nvz/7/
abbreviateNumber(999999) == '1000k'而不是'1M'。这是因为toFixed()还要四舍五入数字。但不确定如何解决问题:/
                    toFixed()仍然将数字四舍五入,您最好在将数字发送给之前将其四舍五入abbreviateNumber(),因此它会返回1M而不是1000k。不是解决方案,而是解决方法。
                    const floored = Math.floor(scaled * 10) / 10;
                    ES2020在Intl.NumberFormat使用表示法中对此添加了支持,如下所示:
console.log(Intl.NumberFormat('en-US', { notation: "compact" , compactDisplay: "short" }).format(987654321));
NumberFormat 眼镜: 
请注意,目前并非所有浏览器都支持ES2020,因此您可能需要以下Polyfill:https ://formatjs.io/docs/polyfills/intl-numberformat
notation和,compactDisplay但是FireFox 77和Safari 13.1仍然不支持它,因此您可能需要使用polyfill。
                    这是相当优雅的。
function formatToUnits(number, precision) {
  const abbrev = ['', 'k', 'm', 'b', 't'];
  const unrangifiedOrder = Math.floor(Math.log10(Math.abs(number)) / 3)
  const order = Math.max(0, Math.min(unrangifiedOrder, abbrev.length -1 ))
  const suffix = abbrev[order];
  return (number / Math.pow(10, order * 3)).toFixed(precision) + suffix;
}
formatToUnits(12345, 2)
==> "12.35k"
formatToUnits(0, 3)
==> "0.000"
              使用负数支持进一步改善@Yash的答案:
function nFormatter(num) {
    isNegative = false
    if (num < 0) {
        isNegative = true
    }
    num = Math.abs(num)
    if (num >= 1000000000) {
        formattedNumber = (num / 1000000000).toFixed(1).replace(/\.0$/, '') + 'G';
    } else if (num >= 1000000) {
        formattedNumber =  (num / 1000000).toFixed(1).replace(/\.0$/, '') + 'M';
    } else  if (num >= 1000) {
        formattedNumber =  (num / 1000).toFixed(1).replace(/\.0$/, '') + 'K';
    } else {
        formattedNumber = num;
    }   
    if(isNegative) { formattedNumber = '-' + formattedNumber }
    return formattedNumber;
}
nFormatter(-120000)
"-120K"
nFormatter(120000)
"120K"
              这篇文章已经很老了,但是我却以某种方式到达了该文章中寻找内容。所以添加我的输入数字js是现在的一站式解决方案。它提供了许多方法来帮助格式化数字
您可以根据需要将COUNT_FORMATS配置对象的长度设置为长或短,具体取决于测试值的范围。
// Configuration    
const COUNT_FORMATS =
[
  { // 0 - 999
    letter: '',
    limit: 1e3
  },
  { // 1,000 - 999,999
    letter: 'K',
    limit: 1e6
  },
  { // 1,000,000 - 999,999,999
    letter: 'M',
    limit: 1e9
  },
  { // 1,000,000,000 - 999,999,999,999
    letter: 'B',
    limit: 1e12
  },
  { // 1,000,000,000,000 - 999,999,999,999,999
    letter: 'T',
    limit: 1e15
  }
];
    
// Format Method:
function formatCount(value)
{
  const format = COUNT_FORMATS.find(format => (value < format.limit));
  value = (1000 * value / format.limit);
  value = Math.round(value * 10) / 10; // keep one decimal number, only if needed
  return (value + format.letter);
}
// Test:
const test = [274, 1683, 56512, 523491, 9523489, 5729532709, 9421032489032];
test.forEach(value => console.log(`${ value } >>> ${ formatCount(value) }`));
Waylon Flinn答案的修改版,支持负指数:
function metric(number) {
  const SI_SYMBOL = [
    ["", "k", "M", "G", "T", "P", "E"], // +
    ["", "m", "μ", "n", "p", "f", "a"] // -
  ];
  const tier = Math.floor(Math.log10(Math.abs(number)) / 3) | 0;
  const n = tier < 0 ? 1 : 0;
  const t = Math.abs(tier);
  const scale = Math.pow(10, tier * 3);
  return {
    number: number,
    symbol: SI_SYMBOL[n][t],
    scale: scale,
    scaled: number / scale
  }
}
function metric_suffix(number, precision) {
  const m = metric(number);
  return (typeof precision === 'number' ? m.scaled.toFixed(precision) : m.scaled) + m.symbol;
}
for (var i = 1e-6, s = 1; i < 1e7; i *= 10, s *= -1) {
  // toggles sign in each iteration
  console.log(metric_suffix(s * (i + i / 5), 1));
}
console.log(metric(0));
预期产量:
   1.2μ
 -12.0μ
 120.0μ
  -1.2m
  12.0m
-120.0m
   1.2
 -12.0
 120.0
  -1.2k
  12.0k
-120.0k
   1.2M
{ number: 0, symbol: '', scale: 1, scaled: 0 }
              !Number.isFinite' K M G T P E Z Y'到' K M',如果你想最大单位M下面的代码是1K = 1024,如果要1K = 1000,请将所有1024更改为1000。
Number.prototype.prefix = function (precision = 2) {
    var units = ' K M G T P E Z Y'.split(' ');
    if (this < 0) {
        return '-' + Math.abs(this).prefix(precision);
    }
    if (this < 1) {
        return this + units[0];
    }
    var power = Math.min(
        Math.floor(Math.log(this) / Math.log(1024)),
        units.length - 1
    );
    return (this / Math.pow(1024, power)).toFixed(precision) + units[power];
}
console.log('10240 = ' + (10240).prefix()) // 10.00K
console.log('1234000 = ' + (1234000).prefix(1)) // 1.2M
console.log('10000 = ' + (-10000).prefix()) // -9.77K
进一步改善@tfmontague的答案以设置小数位格式。33.0k至33k
largeNumberFormatter(value: number): any {
   let result: any = value;
   if (value >= 1e3 && value < 1e6) { result = (value / 1e3).toFixed(1).replace(/\.0$/, '') + 'K'; }
   if (value >= 1e6 && value < 1e9) { result = (value / 1e6).toFixed(1).replace(/\.0$/, '') + 'M'; }
   if (value >= 1e9) { result = (value / 1e9).toFixed(1).replace(/\.0$/, '') + 'T'; }
   return result;
}
              不满意任何发布的解决方案,所以这是我的版本:
支持精度参数
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+$/,'$2') + SI_SYMBOLS[expK+BASE0_OFFSET].trim();
}
//////////////////
const tests = [
  [0.0000000000001,2],
  [0.00000000001,2],
  [0.000000001,2],
  [0.000001,2],
  [0.001,2],
  [0.0016,2],
  [-0.0016,2],
  [0.01,2],
  [1,2],
  [999.99,2],
  [999.99,1],
  [-999.99,1],
  [999999,2],
  [999999999999,2],
  [999999999999999999,2],
  [99999999999999999999,2],
];
for (var i = 0; i < tests.length; i++) {
  console.log(abbreviateNumber(tests[i][0], tests[i][1]) );
}
由于类似nFormatter(999999,1)的情况返回1000K,因此进一步改进了Salman的答案。
function formatNumberWithMetricPrefix(num, digits = 1) {
  const si = [
    {value: 1e18, symbol: 'E'},
    {value: 1e15, symbol: 'P'},
    {value: 1e12, symbol: 'T'},
    {value: 1e9, symbol: 'G'},
    {value: 1e6, symbol: 'M'},
    {value: 1e3, symbol: 'k'},
    {value: 0, symbol: ''},
  ];
  const rx = /\.0+$|(\.[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, '$1') + symbol;
}
              最简单,最简单的方法是
new Intl.NumberFormat('en-IN', { 
    notation: "compact",
    compactDisplay: "short",
    style: 'currency',
    currency: 'INR'
}).format(1000).replace("T", "K")
这适用于任何数量。包括L Cr等
通过消除@ martin-sznapka解决方案中的循环,可以将执行时间减少40%。
function formatNum(num,digits) {
    let units = ['k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'];
    let floor = Math.floor(Math.abs(num).toString().length / 3);
    let value=+(num / Math.pow(1000, floor))
    return value.toFixed(value > 1?digits:2) + units[floor - 1];
}
针对此线程的不同解决方案进行速度测试(200000个随机样本)
Execution time: formatNum          418  ms
Execution time: kFormatter         438  ms it just use "k" no "M".."T" 
Execution time: beautify           593  ms doesnt support - negatives
Execution time: shortenLargeNumber 682  ms    
Execution time: Intl.NumberFormat  13197ms 
              /*including negative values*/    
function nFormatter(num) {
      let neg = false;
       if(num < 0){
         num = num * -1;
         neg = true;
       }
       if (num >= 1000000000) {
         if(neg){
           return -1 * (num / 1000000000).toFixed(1).replace(/\.0$/, '') + '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;
    }
              此函数可以将大量数字(正数和负数)转换为易于阅读的格式,而不会失去精度:
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);
我正在使用此功能。它适用于php和javascript。
    /**
     * @param $n
     * @return string
     * Use to convert large positive numbers in to short form like 1K+, 100K+, 199K+, 1M+, 10M+, 1B+ etc
     */
 function num_format($n) {
        $n_format = null;
        $suffix = null;
        if ($n > 0 && $n < 1000) {
           $n_format = Math.floor($n);   
            $suffix = '';
        }
        else if ($n == 1000) {
            $n_format = Math.floor($n / 1000);   //For PHP only use floor function insted of Math.floor()
            $suffix = 'K';
        }
        else if ($n > 1000 && $n < 1000000) {
            $n_format = Math.floor($n / 1000);
            $suffix = 'K+';
        } else if ($n == 1000000) {
            $n_format = Math.floor($n / 1000000);
            $suffix = 'M';
        } else if ($n > 1000000 && $n < 1000000000) {
            $n_format = Math.floor($n / 1000000);
            $suffix = 'M+';
        } else if ($n == 1000000000) {
            $n_format = Math.floor($n / 1000000000);
            $suffix = 'B';
        } else if ($n > 1000000000 && $n < 1000000000000) {
            $n_format = Math.floor($n / 1000000000);
            $suffix = 'B+';
        } else if ($n == 1000000000000) {
            $n_format = Math.floor($n / 1000000000000);
            $suffix = 'T';
        } else if ($n >= 1000000000000) {
            $n_format = Math.floor($n / 1000000000000);
            $suffix = 'T+';
        }
       /***** For PHP  ******/
       //  return !empty($n_format . $suffix) ? $n_format . $suffix : 0;
       /***** For Javascript ******/
        return ($n_format + $suffix).length > 0 ? $n_format + $suffix : 0;
    }
              我决定在此扩展@Novellizator的答案,以满足我的需求。我想要一个灵活的功能来处理大多数格式化需求,而无需外部库。
let x = 1234567.8;
formatNumber(x);  // '1,234,568'
formatNumber(x, {useOrderSuffix: true});  // '1M'
formatNumber(x, {useOrderSuffix: true, decimals: 3, maxOrder: 1});  // '1,234.568k'
formatNumber(x, {decimals: 2, style: '$'});  // '$1,234,567.80'
x = 10.615;
formatNumber(x, {style: '%'});  // '1,062%'
formatNumber(x, {useOrderSuffix: true, decimals: 1, style: '%'});  // '1.1k%'
formatNumber(x, {useOrderSuffix: true, decimals: 5, style: '%', minOrder: 2});  // '0.00106M%'
formatNumber(-Infinity);  // '-∞'
formatNumber(NaN);  // ''
formatNumber(NaN, {valueIfNaN: NaN});  // NaN
/*
 * Return the given number as a formatted string.  The default format is a plain
 * integer with thousands-separator commas.  The optional parameters facilitate
 * other formats:
 *   - decimals = the number of decimals places to round to and show
 *   - valueIfNaN = the value to show for non-numeric input
 *   - style
 *     - '%': multiplies by 100 and appends a percent symbol
 *     - '$': prepends a dollar sign
 *   - useOrderSuffix = whether to use suffixes like k for 1,000, etc.
 *   - orderSuffixes = the list of suffixes to use
 *   - minOrder and maxOrder allow the order to be constrained.  Examples:
 *     - minOrder = 1 means the k suffix should be used for numbers < 1,000
 *     - maxOrder = 1 means the k suffix should be used for numbers >= 1,000,000
 */
function formatNumber(number, {
    decimals = 0,
    valueIfNaN = '',
    style = '',
    useOrderSuffix = false,
    orderSuffixes = ['', 'k', 'M', 'B', 'T'],
    minOrder = 0,
    maxOrder = Infinity
  } = {}) {
  let x = parseFloat(number);
  if (isNaN(x))
    return valueIfNaN;
  if (style === '%')
    x *= 100.0;
  let order;
  if (!isFinite(x) || !useOrderSuffix)
    order = 0;
  else if (minOrder === maxOrder)
    order = minOrder;
  else {
    const unboundedOrder = Math.floor(Math.log10(Math.abs(x)) / 3);
    order = Math.max(
      0,
      minOrder,
      Math.min(unboundedOrder, maxOrder, orderSuffixes.length - 1)
    );
  }
  const orderSuffix = orderSuffixes[order];
  if (order !== 0)
    x /= Math.pow(10, order * 3);
  return (style === '$' ? '$' : '') +
    x.toLocaleString(
      'en-US',
      {
        style: 'decimal',
        minimumFractionDigits: decimals,
        maximumFractionDigits: decimals
      }
    ) +
    orderSuffix +
    (style === '%' ? '%' : '');
}
              哇,这里有很多答案。我想我会给你我如何解决它的方法,因为它似乎最容易阅读,处理负数,并且远远超出了JavaScript的千位数范围。更改为您想要的内容或将其扩展到其他位置也很容易。
const symbols = [
  { 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' }
];
function numberFormatter(num, digits) {
  const numToCheck = Math.abs(num);
  for (let i = symbols.length - 1; i >= 0; i--) {
    if (numToCheck >= symbols[i].value) {
      const newNumber = (num / symbols[i].value).toFixed(digits);
      return `${newNumber}${symbols[i].symbol}`;
    }
  }
  return '0';
}
const tests = [
  { 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 }
];
for (let i = 0; i < tests.length; i++) {
  console.log(`numberFormatter(${tests[i].num}, ${tests[i].digits})=${numberFormatter(tests[i].num, tests[i].digits)}`);
}
一个更短的选择:
function nFormatter(num) {
    const format = [
      { 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: 1, symbol: '' },
    ];
    const formatIndex = format.findIndex((data) => num >= data.value);
    console.log(formatIndex)
    return (num / format[formatIndex === -1? 6: formatIndex].value).toFixed(2) + format[formatIndex === -1?6: formatIndex].symbol;
  }
  
M和G?