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
只需使用本机javascript Intl
您只需使用选项设置其值的格式
常量编号=1233445.5678console.log(新的Intl.NumberFormat('en-US',{style:'currency',currency:'USD'}).format(数字));
mozilla文档链接
其他回答
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 + "\"");
}
}
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。
下面是Patrick Desjardins(别名Daok)代码,添加了一些注释和一些小改动:
/*
decimal_sep: character used as decimal separator, it defaults to '.' when omitted
thousands_sep: char used as thousands separator, it defaults to ',' when omitted
*/
Number.prototype.toMoney = function(decimals, decimal_sep, thousands_sep)
{
var n = this,
c = isNaN(decimals) ? 2 : Math.abs(decimals), // If decimal is zero we must take it. It means the user does not want to show any decimal
d = decimal_sep || '.', // If no decimal separator is passed, we use the dot as default decimal separator (we MUST use a decimal separator)
/*
According to [https://stackoverflow.com/questions/411352/how-best-to-determine-if-an-argument-is-not-sent-to-the-javascript-function]
the fastest way to check for not defined parameter is to use typeof value === 'undefined'
rather than doing value === undefined.
*/
t = (typeof thousands_sep === 'undefined') ? ',' : thousands_sep, // If you don't want to use a thousands separator you can pass empty string as thousands_sep value
sign = (n < 0) ? '-' : '',
// Extracting the absolute value of the integer part of the number and converting to string
i = parseInt(n = Math.abs(n).toFixed(c)) + '',
j = ((j = i.length) > 3) ? j % 3 : 0;
return sign + (j ? i.substr(0, j) + t : '') + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : '');
}
这里有一些测试:
// Some tests (do not forget parenthesis when using negative numbers and number with no decimals)
alert(123456789.67392.toMoney() + '\n' + 123456789.67392.toMoney(3) + '\n' + 123456789.67392.toMoney(0) + '\n' + (123456).toMoney() + '\n' + (123456).toMoney(0) + '\n' + 89.67392.toMoney() + '\n' + (89).toMoney());
// Some tests (do not forget parenthesis when using negative numbers and number with no decimals)
alert((-123456789.67392).toMoney() + '\n' + (-123456789.67392).toMoney(-3));
次要变化包括:
移动了一点Math.abs(小数),只有当不是NaN时才能执行。decimal_sep不能再是空字符串(必须使用某种十进制分隔符)我们使用typeof thousand_sep===“undefined”,如How best to determine if a argument is not send to JavaScript function中所建议的不需要(+n||0),因为这是Number对象
JSFiddle公司
我想你想要:
f.nettotal.value = "$" + showValue.toFixed(2);
Patrick热门答案的CoffeeScript:
Number::formatMoney = (decimalPlaces, decimalChar, thousandsChar) ->
n = this
c = decimalPlaces
d = decimalChar
t = thousandsChar
c = (if isNaN(c = Math.abs(c)) then 2 else c)
d = (if d is undefined then "." else d)
t = (if t is undefined then "," else t)
s = (if n < 0 then "-" else "")
i = parseInt(n = Math.abs(+n or 0).toFixed(c)) + ""
j = (if (j = i.length) > 3 then j % 3 else 0)
s + (if j then i.substr(0, j) + t else "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (if c then d + Math.abs(n - i).toFixed(c).slice(2) else "")