這里第二個(gè)方法是用簡(jiǎn)單的正則表達(dá)式將貨幣字符換轉(zhuǎn)換為純凈的數(shù)字字符串，之后便可以將字符串轉(zhuǎn)換為數(shù)字number
JavaScript Money Format（用prototype對(duì)Number進(jìn)行擴(kuò)展）

// Extend the default Number object with a formatMoney() method:
// usage: someVar.formatMoney(decimalPlaces, symbol, thousandsSeparator, decimalSeparator)
// defaults: (2, "$", ",", ".")
Number.prototype.formatMoney = function (places, symbol, thousand, decimal) {
  places = !isNaN(places = Math.abs(places)) ? places : 2;
  symbol = symbol !== undefined ? symbol : "$";
  thousand = thousand || ",";
  decimal = decimal || ".";
  var number = this,
    negative = number < 0 ? "-" : "",
    i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + "",
    j = (j = i.length) > 3 ? j % 3 : 0;
  return symbol + negative + (j ? i.substr(0, j) + thousand : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousand) + (places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : "");
};

如下便是一些轉(zhuǎn)換實(shí)例：

// Default usage and custom precision/symbol :
var revenue = 12345678;
alert(revenue.formatMoney()); // $12,345,678.00
alert(revenue.formatMoney(0, "HK$ ")); // HK$ 12,345,678

// European formatting:
var price = 4999.99;
alert(price.formatMoney(2, "€", ".", ",")); // €4.999,99

// It works for negative values, too:
alert((-500000).formatMoney(0, "£ ")); // £ -500,000

Currency to number – removing money formatting （用正則表達(dá)式進(jìn)行過(guò)濾）

var price = (12345.99).formatMoney(); // "$12,345.99"

// Remove non-numeric chars (except decimal point/minus sign):
priceVal = parseFloat(price.replace(/[^0-9-.]/g, '')); // 12345.99

這個(gè)方法僅僅應(yīng)用于小數(shù)分隔符為"."的模式，如果小數(shù)分隔符是"," 那么正則表達(dá)式為/[^0-9-,]/g

不用prototype對(duì)Number進(jìn)行拓展的版本：

// To set it up as a global function:
function formatMoney(number, places, symbol, thousand, decimal) {
  number = number || 0;
  places = !isNaN(places = Math.abs(places)) ? places : 2;
  symbol = symbol !== undefined ? symbol : "$";
  thousand = thousand || ",";
  decimal = decimal || ".";
  var negative = number < 0 ? "-" : "",
    i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + "",
    j = (j = i.length) > 3 ? j % 3 : 0;
  return symbol + negative + (j ? i.substr(0, j) + thousand : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousand) + (places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : "");
}

// To create it as a library method:
myLibrary.formatMoney = function (number, places, symbol, thousand, decimal) {
  /* as above */
}

// Example usage:
formatMoney(54321); // $54,321
myLibrary.formatMoney(12345, 0, "£ "); // £ 12,345

以上就是本文的全部?jī)?nèi)容，了解更多JavaScript的語(yǔ)法，大家可以查看：《JavaScript 參考教程》、《JavaScript代碼風(fēng)格指南》，也希望大家多多支持腳本之家。

您可能感興趣的文章: