我想用JavaScript格式化价格。我想要一个函数,它将浮点作为参数,并返回如下格式的字符串:

"$ 2,500.00"

我该怎么做?


当前回答

+1向Jonathan M提供原始方法。由于这是一个明确的货币格式化程序,我继续在输出中添加了货币符号(默认为“$”),并添加了一个默认逗号作为千位分隔符。如果您实际上不需要货币符号(或千位分隔符),只需使用“”(空字符串)作为它的参数。

Number.prototype.formatMoney = function(decPlaces, thouSeparator, decSeparator, currencySymbol) {
    // check the args and supply defaults:
    decPlaces = isNaN(decPlaces = Math.abs(decPlaces)) ? 2 : decPlaces;
    decSeparator = decSeparator == undefined ? "." : decSeparator;
    thouSeparator = thouSeparator == undefined ? "," : thouSeparator;
    currencySymbol = currencySymbol == undefined ? "$" : currencySymbol;

    var n = this,
        sign = n < 0 ? "-" : "",
        i = parseInt(n = Math.abs(+n || 0).toFixed(decPlaces)) + "",
        j = (j = i.length) > 3 ? j % 3 : 0;

    return sign + currencySymbol + (j ? i.substr(0, j) + thouSeparator : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thouSeparator) + (decPlaces ? decSeparator + Math.abs(n - i).toFixed(decPlaces).slice(2) : "");
};

其他回答

数字.原型.固定

此解决方案与每个主要浏览器都兼容:

  const profits = 2489.8237;

  profits.toFixed(3) // Returns 2489.824 (rounds up)
  profits.toFixed(2) // Returns 2489.82
  profits.toFixed(7) // Returns 2489.8237000 (pads the decimals)

您只需添加货币符号(例如“$”+利润.toFixed(2)),即可获得美元金额。

自定义函数

如果需要在每个数字之间使用,则可以使用此函数:

函数格式Money(number,decPlaces,decSep,thouSep){decPlaces=isNaN(decPlaces=数学.abs(decPlaces))?2:decPlaces,decSep=decSep的类型==“未定义”?“.”:12月9日;thouSep=thouSep==“未定义”的类型?“,”:thouSep;var符号=数字<0?"-" : "";var i=字符串(parseInt(number=Math.abs(number(number)||0).toFixed(decPlaces)));变量j=(j=i.length)>3?j%3:0;返回标志+(j?i.substr(0,j)+thouSep:“”)+i.substr(j).replace(/(\decSep{3})(?=\decSep)/g,“$1”+thouSep)+(decPlaces?decSep+Math.abs(数字-i).toFixed(decPlace).slice(2):“”);}document.getElementById(“b”).addEventListener(“单击”,event=>{document.getElementById(“x”).innerText=“结果为:”+formatMoney(document.getElement ById(”d“).value);});<label>插入您的金额:<input id=“d”type=“text”placeholder=“Cash amount”/></label><br/><button id=“b”>获取输出</button><p id=“x”>(按下按钮获取输出)</p>

这样使用:

(123456789.12345).formatMoney(2, ".", ",");

如果你总是使用“.”和',',您可以将它们从方法调用中删除,方法将为您默认它们。

(123456789.12345).formatMoney(2);

如果您的文化中有两个符号翻转(即,欧洲人),并且您希望使用默认值,只需在formatMoney方法中粘贴以下两行:

    d = d == undefined ? "," : d,
    t = t == undefined ? "." : t,

自定义功能(ES6)

如果您可以使用现代ECMAScript语法(即,通过Babel),则可以使用更简单的函数:

函数formatMoney(amount,decimalCount=2,decimal=“.”,千=“,”){尝试{decimalCount=数学.abs(decimalCount);decimalCount=isNaN(decimalCount)?2:小数计数;常量负符号=金额<0?"-" : "";让i=parseInt(amount=Math.abs(Number(amount)||0).toFixed(decimalCount)).toString();设j=(i.length>3)?i.长度%3:0;回来否定符号+(j?i.substr(0,j)+千:“”)+i.substr(j).replace(/(\d{3})(?=\d)/g,“$1”+千)+(decimalCount?decimal+Math.abs(amount-i).toFixed(decimalCount).slice(2):“”);}捕获(e){控制台日志(e)}};document.getElementById(“b”).addEventListener(“单击”,event=>{document.getElementById(“x”).innerText=“结果为:”+formatMoney(document.getElement ById(”d“).value);});<label>插入您的金额:<input id=“d”type=“text”placeholder=“Cash amount”/></label><br/><button id=“b”>获取输出</button><p id=“x”>(按下按钮获取输出)</p>

accounting.js是一个用于数字、货币和货币格式的小型JavaScript库。

http://code.google.com/p/javascript-number-formatter/:

短、快、灵活但独立。只有75行,包括MIT许可证信息、空白行和注释。接受标准数字格式,如#、##0.00或带否定的-000.####。接受任何国家/地区格式,如###0,00,#,###.##,#‘###.##或任何类型的非编号符号。接受任意数字分组。#、##、#0.000或#、####0.##均有效。接受任何冗余/防傻瓜格式。##、###、##。#或0#、#00####0#都正常。自动数字舍入。简单的界面,只需提供如下掩码和值:格式(“0.0000”,3.141592)

UPDATE这是我自己开发的应用程序,用于最常见的任务:

var NumUtil = {};

/**
  Petty print 'num' wth exactly 'signif' digits.
  pp(123.45, 2) == "120"
  pp(0.012343, 3) == "0.0123"
  pp(1.2, 3) == "1.20"
*/
NumUtil.pp = function(num, signif) {
    if (typeof(num) !== "number")
        throw 'NumUtil.pp: num is not a number!';
    if (isNaN(num))
        throw 'NumUtil.pp: num is NaN!';
    if (num < 1e-15 || num > 1e15)
        return num;
    var r = Math.log(num)/Math.LN10;
    var dot = Math.floor(r) - (signif-1);
    r = r - Math.floor(r) + (signif-1);
    r = Math.round(Math.exp(r * Math.LN10)).toString();
    if (dot >= 0) {
        for (; dot > 0; dot -= 1)
            r += "0";
        return r;
    } else if (-dot >= r.length) {
        var p = "0.";
        for (; -dot > r.length; dot += 1) {
            p += "0";
        }
        return p+r;
    } else {
        return r.substring(0, r.length + dot) + "." + r.substring(r.length + dot);
    }
}

/** Append leading zeros up to 2 digits. */
NumUtil.align2 = function(v) {
    if (v < 10)
        return "0"+v;
    return ""+v;
}
/** Append leading zeros up to 3 digits. */
NumUtil.align3 = function(v) {
    if (v < 10)
        return "00"+v;
    else if (v < 100)
        return "0"+v;
    return ""+v;
}

NumUtil.integer = {};

/** Round to integer and group by 3 digits. */
NumUtil.integer.pp = function(num) {
    if (typeof(num) !== "number") {
        console.log("%s", new Error().stack);
        throw 'NumUtil.integer.pp: num is not a number!';
    }
    if (isNaN(num))
        throw 'NumUtil.integer.pp: num is NaN!';
    if (num > 1e15)
        return num;
    if (num < 0)
        throw 'Negative num!';
    num = Math.round(num);
    var group = num % 1000;
    var integ = Math.floor(num / 1000);
    if (integ === 0) {
        return group;
    }
    num = NumUtil.align3(group);
    while (true) {
        group = integ % 1000;
        integ = Math.floor(integ / 1000);
        if (integ === 0)
            return group + " " + num;
        num = NumUtil.align3(group) + " " + num;
    }
    return num;
}

NumUtil.currency = {};

/** Round to coins and group by 3 digits. */
NumUtil.currency.pp = function(amount) {
    if (typeof(amount) !== "number")
        throw 'NumUtil.currency.pp: amount is not a number!';
    if (isNaN(amount))
        throw 'NumUtil.currency.pp: amount is NaN!';
    if (amount > 1e15)
        return amount;
    if (amount < 0)
        throw 'Negative amount!';
    if (amount < 1e-2)
        return 0;
    var v = Math.round(amount*100);
    var integ = Math.floor(v / 100);
    var frac = NumUtil.align2(v % 100);
    var group = integ % 1000;
    integ = Math.floor(integ / 1000);
    if (integ === 0) {
        return group + "." + frac;
    }
    amount = NumUtil.align3(group);
    while (true) {
        group = integ % 1000;
        integ = Math.floor(integ / 1000);
        if (integ === 0)
            return group + " " + amount + "." + frac;
        amount = NumUtil.align3(group) + " " + amount;
    }
    return amount;
}
function CurrencyFormatted(amount)
{
    var i = parseFloat(amount);
    if(isNaN(i)) { i = 0.00; }
    var minus = '';
    if(i < 0) { minus = '-'; }
    i = Math.abs(i);
    i = parseInt((i + .005) * 100);
    i = i / 100;
    s = new String(i);
    if(s.indexOf('.') < 0) { s += '.00'; }
    if(s.indexOf('.') == (s.length - 2)) { s += '0'; }
    s = minus + s;
    return s;
}

来自WillMaster。

这可能有点晚了,但这是我刚刚为同事准备的一个方法,可以为所有数字添加一个支持区域设置的.toCurrencyString()函数。内部化仅用于数字分组,而不是货币符号-如果您输出美元,请使用提供的“$”,因为日本或中国的123 4567美元与美国的1234567美元相同。如果您输出欧元等,请将货币符号从“$”改为“$”。

在HTML<head>部分的任何地方或在需要使用它之前的任何地方声明:

  Number.prototype.toCurrencyString = function(prefix, suffix) {
    if (typeof prefix === 'undefined') { prefix = '$'; }
    if (typeof suffix === 'undefined') { suffix = ''; }
    var _localeBug = new RegExp((1).toLocaleString().replace(/^1/, '').replace(/\./, '\\.') + "$");
    return prefix + (~~this).toLocaleString().replace(_localeBug, '') + (this % 1).toFixed(2).toLocaleString().replace(/^[+-]?0+/,'') + suffix;
  }

那你就完了!在需要将数字输出为货币的任何位置使用(number).toCurrencyString()。

var MyNumber = 123456789.125;
alert(MyNumber.toCurrencyString()); // alerts "$123,456,789.13"
MyNumber = -123.567;
alert(MyNumber.toCurrencyString()); // alerts "$-123.57"