JS將number數值轉化成為貨幣格式

JS將number數值轉化成為貨幣格式：

這里第一個方法是用JavaScript將數字number轉換為貨幣字符串的格式(參數：保留小數位數，貨幣符號，整數部分千位分隔符，小數分隔符)

這里第二個方法是用簡單的正則表達式將貨幣字符換轉換為純凈的數字字符串，之后便可以將字符串轉換為數字number

JavaScript Money Format（用prototype對Number進行擴展）

// 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) : "");
    };

 

如下便是一些轉換實例：

    // 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 （用正則表達式進行過濾）

    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

這個方法僅僅應用於小數分隔符為"."的模式，如果小數分隔符是"," 那么正則表達式為/[^0-9-,]/g

 

不用prototype對Number進行拓展的版本：

    // 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