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
如果金额是一个数字，比如-123，那么
amount.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
将生成字符串“-123.00”。
这是一个完整的工作示例。
其他回答
这可能奏效：
function format_currency(v, number_of_decimals, decimal_separator, currency_sign){
return (isNaN(v)? v : currency_sign + parseInt(v||0).toLocaleString() + decimal_separator + (v*1).toFixed(number_of_decimals).slice(-number_of_decimals));
}
没有循环，没有正则表达式，没有数组，没有奇异条件。
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"
请在下面的代码中找到我为支持国际化而开发的内容。
它将给定的数值格式化为特定于语言的格式。在给定的示例中，我使用了“en”，同时测试了“es”、“fr”和其他格式不同的国家。它不仅可以阻止用户键入字符，还可以格式化制表符上的值。
我已经为数字和十进制格式创建了组件。除此之外，我还创建了parseNumber（value，locale）和parseDecimal（value，locale）函数，这些函数将解析格式化数据以用于任何其他业务目的。所述函数将接受格式化数据并返回非格式化值。我在下面的共享代码中使用了jQuery验证器插件。
HTML格式：
<tr>
<td>
<label class="control-label">
Number Field:
</label>
<div class="inner-addon right-addon">
<input type="text" id="numberField"
name="numberField"
class="form-control"
autocomplete="off"
maxlength="17"
data-rule-required="true"
data-msg-required="Cannot be blank."
data-msg-maxlength="Exceeding the maximum limit of 13 digits. Example: 1234567890123"
data-rule-numberExceedsMaxLimit="en"
data-msg-numberExceedsMaxLimit="Exceeding the maximum limit of 13 digits. Example: 1234567890123"
onkeydown="return isNumber(event, 'en')"
onkeyup="return updateField(this)"
onblur="numberFormatter(this,
'en',
'Invalid character(s) found. Please enter valid characters.')">
</div>
</td>
</tr>
<tr>
<td>
<label class="control-label">
Decimal Field:
</label>
<div class="inner-addon right-addon">
<input type="text" id="decimalField"
name="decimalField"
class="form-control"
autocomplete="off"
maxlength="20"
data-rule-required="true"
data-msg-required="Cannot be blank."
data-msg-maxlength="Exceeding the maximum limit of 16 digits. Example: 1234567890123.00"
data-rule-decimalExceedsMaxLimit="en"
data-msg-decimalExceedsMaxLimit="Exceeding the maximum limit of 16 digits. Example: 1234567890123.00"
onkeydown="return isDecimal(event, 'en')"
onkeyup="return updateField(this)"
onblur="decimalFormatter(this,
'en',
'Invalid character(s) found. Please enter valid characters.')">
</div>
</td>
</tr>
JavaScript：
/*
* @author: dinesh.lomte
*/
/* Holds the maximum limit of digits to be entered in number field. */
var numericMaxLimit = 13;
/* Holds the maximum limit of digits to be entered in decimal field. */
var decimalMaxLimit = 16;
/**
*
* @param {type} value
* @param {type} locale
* @returns {Boolean}
*/
parseDecimal = function(value, locale) {
value = value.trim();
if (isNull(value)) {
return 0.00;
}
if (isNull(locale)) {
return value;
}
if (getNumberFormat(locale)[0] === '.') {
value = value.replace(/\./g, '');
} else {
value = value.replace(
new RegExp(getNumberFormat(locale)[0], 'g'), '');
}
if (getNumberFormat(locale)[1] === ',') {
value = value.replace(
new RegExp(getNumberFormat(locale)[1], 'g'), '.');
}
return value;
};
/**
*
* @param {type} element
* @param {type} locale
* @param {type} nanMessage
* @returns {Boolean}
*/
decimalFormatter = function (element, locale, nanMessage) {
showErrorMessage(element.id, false, null);
if (isNull(element.id) || isNull(element.value) || isNull(locale)) {
return true;
}
var value = element.value.trim();
value = value.replace(/\s/g, '');
value = parseDecimal(value, locale);
var numberFormatObj = new Intl.NumberFormat(locale,
{ minimumFractionDigits: 2,
maximumFractionDigits: 2
}
);
if (numberFormatObj.format(value) === 'NaN') {
showErrorMessage(element.id, true, nanMessage);
setFocus(element.id);
return false;
}
element.value = numberFormatObj.format(value);
return true;
};
/**
*
* @param {type} element
* @param {type} locale
* @param {type} nanMessage
* @returns {Boolean}
*/
numberFormatter = function (element, locale, nanMessage) {
showErrorMessage(element.id, false, null);
if (isNull(element.id) || isNull(element.value) || isNull(locale)) {
return true;
}
var value = element.value.trim();
var format = getNumberFormat(locale);
if (hasDecimal(value, format[1])) {
showErrorMessage(element.id, true, nanMessage);
setFocus(element.id);
return false;
}
value = value.replace(/\s/g, '');
value = parseNumber(value, locale);
var numberFormatObj = new Intl.NumberFormat(locale,
{ minimumFractionDigits: 0,
maximumFractionDigits: 0
}
);
if (numberFormatObj.format(value) === 'NaN') {
showErrorMessage(element.id, true, nanMessage);
setFocus(element.id);
return false;
}
element.value =
numberFormatObj.format(value);
return true;
};
/**
*
* @param {type} id
* @param {type} flag
* @param {type} message
* @returns {undefined}
*/
showErrorMessage = function(id, flag, message) {
if (flag) {
// only add if not added
if ($('#'+id).parent().next('.app-error-message').length === 0) {
var errorTag = '<div class=\'app-error-message\'>' + message + '</div>';
$('#'+id).parent().after(errorTag);
}
} else {
// remove it
$('#'+id).parent().next(".app-error-message").remove();
}
};
/**
*
* @param {type} id
* @returns
*/
setFocus = function(id) {
id = id.trim();
if (isNull(id)) {
return;
}
setTimeout(function() {
document.getElementById(id).focus();
}, 10);
};
/**
*
* @param {type} value
* @param {type} locale
* @returns {Array}
*/
parseNumber = function(value, locale) {
value = value.trim();
if (isNull(value)) {
return 0;
}
if (isNull(locale)) {
return value;
}
if (getNumberFormat(locale)[0] === '.') {
return value.replace(/\./g, '');
}
return value.replace(
new RegExp(getNumberFormat(locale)[0], 'g'), '');
};
/**
*
* @param {type} locale
* @returns {Array}
*/
getNumberFormat = function(locale) {
var format = [];
var numberFormatObj = new Intl.NumberFormat(locale,
{ minimumFractionDigits: 2,
maximumFractionDigits: 2
}
);
var value = numberFormatObj.format('132617.07');
format[0] = value.charAt(3);
format[1] = value.charAt(7);
return format;
};
/**
*
* @param {type} value
* @param {type} fractionFormat
* @returns {Boolean}
*/
hasDecimal = function(value, fractionFormat) {
value = value.trim();
if (isNull(value) || isNull(fractionFormat)) {
return false;
}
if (value.indexOf(fractionFormat) >= 1) {
return true;
}
};
/**
*
* @param {type} event
* @param {type} locale
* @returns {Boolean}
*/
isNumber = function(event, locale) {
var keyCode = event.which ? event.which : event.keyCode;
// Validating if user has pressed shift character
if (keyCode === 16) {
return false;
}
if (isNumberKey(keyCode)) {
return true;
}
var numberFormatter = [32, 110, 188, 190];
if (keyCode === 32
&& isNull(getNumberFormat(locale)[0]) === isNull(getFormat(keyCode))) {
return true;
}
if (numberFormatter.indexOf(keyCode) >= 0
&& getNumberFormat(locale)[0] === getFormat(keyCode)) {
return true;
}
return false;
};
/**
*
* @param {type} event
* @param {type} locale
* @returns {Boolean}
*/
isDecimal = function(event, locale) {
var keyCode = event.which ? event.which : event.keyCode;
// Validating if user has pressed shift character
if (keyCode === 16) {
return false;
}
if (isNumberKey(keyCode)) {
return true;
}
var numberFormatter = [32, 110, 188, 190];
if (keyCode === 32
&& isNull(getNumberFormat(locale)[0]) === isNull(getFormat(keyCode))) {
return true;
}
if (numberFormatter.indexOf(keyCode) >= 0
&& (getNumberFormat(locale)[0] === getFormat(keyCode)
|| getNumberFormat(locale)[1] === getFormat(keyCode))) {
return true;
}
return false;
};
/**
*
* @param {type} keyCode
* @returns {Boolean}
*/
isNumberKey = function(keyCode) {
if ((keyCode >= 48 && keyCode <= 57) ||
(keyCode >= 96 && keyCode <= 105)) {
return true;
}
var keys = [8, 9, 13, 35, 36, 37, 39, 45, 46, 109, 144, 173, 189];
if (keys.indexOf(keyCode) !== -1) {
return true;
}
return false;
};
/**
*
* @param {type} keyCode
* @returns {JSON@call;parse.numberFormatter.value|String}
*/
getFormat = function(keyCode) {
var jsonString = '{"numberFormatter" : [{"key":"32", "value":" ", "description":"space"}, {"key":"188", "value":",", "description":"comma"}, {"key":"190", "value":".", "description":"dot"}, {"key":"110", "value":".", "description":"dot"}]}';
var jsonObject = JSON.parse(jsonString);
for (var key in jsonObject.numberFormatter) {
if (jsonObject.numberFormatter.hasOwnProperty(key)
&& keyCode === parseInt(jsonObject.numberFormatter[key].key)) {
return jsonObject.numberFormatter[key].value;
}
}
return '';
};
/**
*
* @type String
*/
var jsonString = '{"shiftCharacterNumberMap" : [{"char":")", "number":"0"}, {"char":"!", "number":"1"}, {"char":"@", "number":"2"}, {"char":"#", "number":"3"}, {"char":"$", "number":"4"}, {"char":"%", "number":"5"}, {"char":"^", "number":"6"}, {"char":"&", "number":"7"}, {"char":"*", "number":"8"}, {"char":"(", "number":"9"}]}';
/**
*
* @param {type} value
* @returns {JSON@call;parse.shiftCharacterNumberMap.number|String}
*/
getShiftCharSpecificNumber = function(value) {
var jsonObject = JSON.parse(jsonString);
for (var key in jsonObject.shiftCharacterNumberMap) {
if (jsonObject.shiftCharacterNumberMap.hasOwnProperty(key)
&& value === jsonObject.shiftCharacterNumberMap[key].char) {
return jsonObject.shiftCharacterNumberMap[key].number;
}
}
return '';
};
/**
*
* @param {type} value
* @returns {Boolean}
*/
isShiftSpecificChar = function(value) {
var jsonObject = JSON.parse(jsonString);
for (var key in jsonObject.shiftCharacterNumberMap) {
if (jsonObject.shiftCharacterNumberMap.hasOwnProperty(key)
&& value === jsonObject.shiftCharacterNumberMap[key].char) {
return true;
}
}
return false;
};
/**
*
* @param {type} element
* @returns {undefined}
*/
updateField = function(element) {
var value = element.value;
for (var index = 0; index < value.length; index++) {
if (!isShiftSpecificChar(value.charAt(index))) {
continue;
}
element.value = value.replace(
value.charAt(index),
getShiftCharSpecificNumber(value.charAt(index)));
}
};
/**
*
* @param {type} value
* @param {type} element
* @param {type} params
*/
jQuery.validator.addMethod('numberExceedsMaxLimit', function(value, element, params) {
value = parseInt(parseNumber(value, params));
if (value.toString().length > numericMaxLimit) {
showErrorMessage(element.id, false, null);
setFocus(element.id);
return false;
}
return true;
}, 'Exceeding the maximum limit of 13 digits. Example: 1234567890123.');
/**
*
* @param {type} value
* @param {type} element
* @param {type} params
*/
jQuery.validator.addMethod('decimalExceedsMaxLimit', function(value, element, params) {
value = parseFloat(parseDecimal(value, params)).toFixed(2);
if (value.toString().substring(
0, value.toString().lastIndexOf('.')).length > numericMaxLimit
|| value.toString().length > decimalMaxLimit) {
showErrorMessage(element.id, false, null);
setFocus(element.id);
return false;
}
return true;
}, 'Exceeding the maximum limit of 16 digits. Example: 1234567890123.00.');
/**
* @param {type} id
* @param {type} locale
* @returns {boolean}
*/
isNumberExceedMaxLimit = function(id, locale) {
var value = parseInt(parseNumber(
document.getElementById(id).value, locale));
if (value.toString().length > numericMaxLimit) {
setFocus(id);
return true;
}
return false;
};
/**
* @param {type} id
* @param {type} locale
* @returns {boolean}
*/
isDecimalExceedsMaxLimit = function(id, locale) {
var value = parseFloat(parseDecimal(
document.getElementById(id).value, locale)).toFixed(2);
if (value.toString().substring(
0, value.toString().lastIndexOf('.')).length > numericMaxLimit
|| value.toString().length > decimalMaxLimit) {
setFocus(id);
return true;
}
return false;
};
JavaScript中没有“formatNumber”的等价物。你可以自己写，也可以找一个已经这样做的库。
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。
