数字（值）.to固定（2）.replace（/（\d）（？=（\d｛3｝）+（？！\d））/g，“$1，”）

此答案符合以下标准：

不依赖于外部依赖项。支持本地化。有测试/证明。使用简单和最佳的编码实践（没有复杂的正则表达式，使用标准的编码模式）。

此代码基于其他答案中的概念。如果这是一个问题的话，它的执行速度应该是最好的。

var decimalCharacter = Number("1.1").toLocaleString().substr(1,1);
var defaultCurrencyMarker = "$";
function formatCurrency(number, currencyMarker) {
    if (typeof number != "number")
        number = parseFloat(number, 10);

    // if NaN is passed in or comes from the parseFloat, set it to 0.
    if (isNaN(number))
        number = 0;

    var sign = number < 0 ? "-" : "";
    number = Math.abs(number);    // so our signage goes before the $ symbol.

    var integral = Math.floor(number);
    var formattedIntegral = integral.toLocaleString();

    // IE returns "##.00" while others return "##"
    formattedIntegral = formattedIntegral.split(decimalCharacter)[0];

    var decimal = Math.round((number - integral) * 100);
    return sign + (currencyMarker || defaultCurrencyMarker) +
        formattedIntegral  +
        decimalCharacter +
        decimal.toString() + (decimal < 10 ? "0" : "");
}

这些测试仅适用于美国语言环境机器。做出这个决定是为了简单，因为这可能会导致糟糕的输入（错误的自动定位），从而导致糟糕的输出问题。

var tests = [
    // [ input, expected result ]
    [123123, "$123,123.00"],    // no decimal
    [123123.123, "$123,123.12"],    // decimal rounded down
    [123123.126, "$123,123.13"],    // decimal rounded up
    [123123.4, "$123,123.40"],    // single decimal
    ["123123", "$123,123.00"],    // repeat subset of the above using string input.
    ["123123.123", "$123,123.12"],
    ["123123.126", "$123,123.13"],
    [-123, "-$123.00"]    // negatives
];

for (var testIndex=0; testIndex < tests.length; testIndex++) {
    var test = tests[testIndex];
    var formatted = formatCurrency(test[0]);
    if (formatted == test[1]) {
        console.log("Test passed, \"" + test[0] + "\" resulted in \"" + formatted + "\"");
    } else {
        console.error("Test failed. Expected \"" + test[1] + "\", got \"" + formatted + "\"");
    }
}

我选择了一些最好的答案，组合并制作了一个通过ESLint的ECMAScript 2015（ES6）函数。

export const formatMoney = (
  amount,
  decimalCount = 2,
  decimal = '.',
  thousands = ',',
  currencySymbol = '$',
) => {
  if (typeof Intl === 'object') {
    return new Intl.NumberFormat('en-AU', {
      style: 'currency',
      currency: 'AUD',
    }).format(amount);
  }
  // Fallback if Intl is not present.
  try {
    const negativeSign = amount < 0 ? '-' : '';
    const amountNumber = Math.abs(Number(amount) || 0).toFixed(decimalCount);
    const i = parseInt(amountNumber, 10).toString();
    const j = i.length > 3 ? i.length % 3 : 0;
    return (
      currencySymbol +
      negativeSign +
      (j ? i.substr(0, j) + thousands : '') +
      i.substr(j).replace(/(\d{3})(?=\d)/g, `$1${thousands}`) +
      (decimalCount
        ? decimal +
          Math.abs(amountNumber - i)
            .toFixed(decimalCount)
            .slice(2)
        : '')
    );
  } catch (e) {
    // eslint-disable-next-line no-console
    console.error(e);
  }
  return amount;
};

toLocaleString很好，但它不适用于所有浏览器。我通常使用currencyFormatter.js(https://osrec.github.io/currencyFormatter.js/). 它非常轻量级，包含所有现成的货币和语言环境定义。它还擅长格式化格式异常的货币，如INR（以10万卢比、10万卢比等为单位分组）。此外，没有任何依赖关系！

OSREC.CurrencyFormatter.format（2534234，｛currency:'INR'｝）；//退换商品₹ 25,34,234.00

OSREC.CurrencyFormatter.format（2534234，｛currency:'EUR'｝）；//退货2.534.234,00欧元

OSREC.CurrencyFormatter.format（2534234，｛currency:'EUR'，locale:'fr'｝）；//退货2 534 234,00欧元

处理货币输出（包括负数）的函数。样本输出：$5.23-$5.23

function formatCurrency(total) {
    var neg = false;
    if(total < 0) {
        neg = true;
        total = Math.abs(total);
    }
    return (neg ? "-$" : '$') + parseFloat(total, 10).toFixed(2).replace(/(\d)(?=(\d{3})+\.)/g, "$1,").toString();
}

我喜欢简单：

function formatPriceUSD(price) {
    var strPrice = price.toFixed(2).toString();
    var a = strPrice.split('');

    if (price > 1000000000)
        a.splice(a.length - 12, 0, ',');

    if (price > 1000000)
        a.splice(a.length - 9, 0, ',');

    if (price > 1000)
        a.splice(a.length - 6, 0, ',');

    return '$' + a.join("");
}