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?
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
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;
}
其他回答
主要部分是插入千个分隔符,可以这样做:
<script type="text/javascript">
function ins1000Sep(val) {
val = val.split(".");
val[0] = val[0].split("").reverse().join("");
val[0] = val[0].replace(/(\d{3})/g, "$1,");
val[0] = val[0].split("").reverse().join("");
val[0] = val[0].indexOf(",") == 0 ? val[0].substring(1) : val[0];
return val.join(".");
}
function rem1000Sep(val) {
return val.replace(/,/g, "");
}
function formatNum(val) {
val = Math.round(val*100)/100;
val = ("" + val).indexOf(".") > -1 ? val + "00" : val + ".00";
var dec = val.indexOf(".");
return dec == val.length-3 || dec == 0 ? val : val.substring(0, dec+3);
}
</script>
<button onclick="alert(ins1000Sep(formatNum(12313231)));">
YUI代码库使用以下格式:
format: function(nData, oConfig) {
oConfig = oConfig || {};
if(!YAHOO.lang.isNumber(nData)) {
nData *= 1;
}
if(YAHOO.lang.isNumber(nData)) {
var sOutput = nData + "";
var sDecimalSeparator = (oConfig.decimalSeparator) ? oConfig.decimalSeparator : ".";
var nDotIndex;
// Manage decimals
if(YAHOO.lang.isNumber(oConfig.decimalPlaces)) {
// Round to the correct decimal place
var nDecimalPlaces = oConfig.decimalPlaces;
var nDecimal = Math.pow(10, nDecimalPlaces);
sOutput = Math.round(nData*nDecimal)/nDecimal + "";
nDotIndex = sOutput.lastIndexOf(".");
if(nDecimalPlaces > 0) {
// Add the decimal separator
if(nDotIndex < 0) {
sOutput += sDecimalSeparator;
nDotIndex = sOutput.length-1;
}
// Replace the "."
else if(sDecimalSeparator !== "."){
sOutput = sOutput.replace(".",sDecimalSeparator);
}
// Add missing zeros
while((sOutput.length - 1 - nDotIndex) < nDecimalPlaces) {
sOutput += "0";
}
}
}
// Add the thousands separator
if(oConfig.thousandsSeparator) {
var sThousandsSeparator = oConfig.thousandsSeparator;
nDotIndex = sOutput.lastIndexOf(sDecimalSeparator);
nDotIndex = (nDotIndex > -1) ? nDotIndex : sOutput.length;
var sNewOutput = sOutput.substring(nDotIndex);
var nCount = -1;
for (var i=nDotIndex; i>0; i--) {
nCount++;
if ((nCount%3 === 0) && (i !== nDotIndex)) {
sNewOutput = sThousandsSeparator + sNewOutput;
}
sNewOutput = sOutput.charAt(i-1) + sNewOutput;
}
sOutput = sNewOutput;
}
// Prepend prefix
sOutput = (oConfig.prefix) ? oConfig.prefix + sOutput : sOutput;
// Append suffix
sOutput = (oConfig.suffix) ? sOutput + oConfig.suffix : sOutput;
return sOutput;
}
// Still not a number. Just return it unaltered
else {
return nData;
}
}
它需要编辑,因为YUI库是可配置的,比如用“.”替换oConfig.decimalSeparator。
使用regexp的更快方法:
Number.prototype.toMonetaryString = function() {
var n = this.toFixed(2), m;
//var = this.toFixed(2).replace(/\./, ','); For comma separator
// with a space for thousands separator
while ((m = n.replace(/(\d)(\d\d\d)\b/g, '$1 $2')) != n)
n = m;
return m;
}
String.prototype.fromMonetaryToNumber = function(s) {
return this.replace(/[^\d-]+/g, '')/100;
}
我使用库Globalize(来自Microsoft):
这是一个很好的项目,可以本地化数字、货币和日期,并根据用户的语言环境以正确的方式自动格式化它们。。。尽管它应该是一个jQuery扩展,但它目前是一个100%独立的库。我建议大家都试试看!:)
看看JavaScriptNumber对象,看看它是否可以帮助您。
toLocaleString()将使用位置特定的千位分隔符格式化数字。toFixed()将数字舍入到特定的小数位数。
要同时使用这些值,必须将其类型改回数字,因为它们都输出字符串。
例子:
Number((someNumber).toFixed(1)).toLocaleString()
EDIT
您可以直接使用toLocaleString,而不必重新转换为数字:
someNumber.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
多个数字
如果需要经常以类似的方式格式化数字,可以创建一个特定的对象以供重用。德语(瑞士):
const money = new Intl.NumberFormat('de-CH',
{ style:'currency', currency: 'CHF' });
const percent = new Intl.NumberFormat('de-CH',
{ style:'percent', maximumFractionDigits: 1, signDisplay: "always"});
其可以用作:
money.format(1234.50); // output CHF 1'234.50
percent.format(0.083); // output +8.3%
非常漂亮。