我需要显示一个货币值的格式1K等于一千,或1.1K, 1.2K, 1.9K等,如果它不是一个偶数千,否则如果低于一千,显示正常500,100,250等,使用JavaScript格式化的数字?
当前回答
通过消除@martin-sznapka解决方案中的循环,您将减少40%的执行时间。
function formatNum(num,digits) {
let units = ['k', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y'];
let floor = Math.floor(Math.abs(num).toString().length / 3);
let value=+(num / Math.pow(1000, floor))
return value.toFixed(value > 1?digits:2) + units[floor - 1];
}
速度测试(200000随机样本)从这个线程不同的解决方案
Execution time: formatNum 418 ms
Execution time: kFormatter 438 ms it just use "k" no "M".."T"
Execution time: beautify 593 ms doesnt support - negatives
Execution time: shortenLargeNumber 682 ms
Execution time: Intl.NumberFormat 13197ms
其他回答
直接的方法具有最好的可读性,并且使用最少的内存。不需要过多地使用regex、map对象、Math对象、for-loops等。
使用K格式化现金值
const formatCash = n => { 如果(n < 1e3)返回n; if (n >= 1e3) return +(n / 1e3).toFixed(1) +“K”; }; console.log (formatCash (2500));
使用K M B T格式化现金值
const formatCash = n => { 如果(n < 1e3)返回n; 如果1 e3 & & n (n > = < 1 e6)返回+ (n / 1 e3) .toFixed(1) +“K”; 如果1 e6 & & n (n > = < 1 e9) + 1 (n / e6)返回.toFixed(1) +“M”; if (n >= 1e9 && n < 1e12) return +(n / 1e9).toFixed(1) + "B"; if (n >= 1e12) return +(n / 1e12).toFixed(1) + "T"; }; console.log (formatCash (1235000));
使用负数
let format;
const number = -1235000;
if (number < 0) {
format = '-' + formatCash(-1 * number);
} else {
format = formatCash(number);
}
function AmountConveter(amount) {
return Math.abs(amount) > 999
? Math.sign(amount) * (Math.abs(amount) / 1000).toFixed(1) + "k"
: Math.sign(amount) * Math.abs(amount);
}
console.log(AmountConveter(1200)); // 1.2k
console.log(AmountConveter(-1200)); // -1.2k
console.log(AmountConveter(900)); // 900
console.log(AmountConveter(-900)); // -900
下面是一个使用for的选项:
函数numberFormat(d) For (var e = 0;D >= 1000;e + +) { D /= 1000; } return d.toFixed(3) + [", ' k', ' M', ' G'][e]; } let s = numberFormat(9012345678); console.log(s == '9.012 G');
这里有一个简单的解决方案,可以避免所有的if语句(借助Math的力量)。
var SI_SYMBOL = ["", "k", "M", "G", "T", "P", "E"];
function abbreviateNumber(number){
// what tier? (determines SI symbol)
var tier = Math.log10(Math.abs(number)) / 3 | 0;
// if zero, we don't need a suffix
if(tier == 0) return number;
// get suffix and determine scale
var suffix = SI_SYMBOL[tier];
var scale = Math.pow(10, tier * 3);
// scale the number
var scaled = number / scale;
// format number and add suffix
return scaled.toFixed(1) + suffix;
}
奖金模因
SI代表什么?
我决定在这里扩展@Novellizator的答案,以满足我的需求。我想要一个灵活的函数来处理我的大部分格式化需求,而不需要外部库。
特性
选择使用顺序后缀(k, M等) 选项指定要使用的订单后缀的自定义列表 选项来约束最小和最大顺序 控制小数点后的位数 自动顺序分隔逗号 可选百分比或美元格式 控制在非数字输入的情况下返回什么 适用于负数和无穷数
例子
let x = 1234567.8;
formatNumber(x); // '1,234,568'
formatNumber(x, {useOrderSuffix: true}); // '1M'
formatNumber(x, {useOrderSuffix: true, decimals: 3, maxOrder: 1}); // '1,234.568k'
formatNumber(x, {decimals: 2, style: '$'}); // '$1,234,567.80'
x = 10.615;
formatNumber(x, {style: '%'}); // '1,062%'
formatNumber(x, {useOrderSuffix: true, decimals: 1, style: '%'}); // '1.1k%'
formatNumber(x, {useOrderSuffix: true, decimals: 5, style: '%', minOrder: 2}); // '0.00106M%'
formatNumber(-Infinity); // '-∞'
formatNumber(NaN); // ''
formatNumber(NaN, {valueIfNaN: NaN}); // NaN
函数
/*
* Return the given number as a formatted string. The default format is a plain
* integer with thousands-separator commas. The optional parameters facilitate
* other formats:
* - decimals = the number of decimals places to round to and show
* - valueIfNaN = the value to show for non-numeric input
* - style
* - '%': multiplies by 100 and appends a percent symbol
* - '$': prepends a dollar sign
* - useOrderSuffix = whether to use suffixes like k for 1,000, etc.
* - orderSuffixes = the list of suffixes to use
* - minOrder and maxOrder allow the order to be constrained. Examples:
* - minOrder = 1 means the k suffix should be used for numbers < 1,000
* - maxOrder = 1 means the k suffix should be used for numbers >= 1,000,000
*/
function formatNumber(number, {
decimals = 0,
valueIfNaN = '',
style = '',
useOrderSuffix = false,
orderSuffixes = ['', 'k', 'M', 'B', 'T'],
minOrder = 0,
maxOrder = Infinity
} = {}) {
let x = parseFloat(number);
if (isNaN(x))
return valueIfNaN;
if (style === '%')
x *= 100.0;
let order;
if (!isFinite(x) || !useOrderSuffix)
order = 0;
else if (minOrder === maxOrder)
order = minOrder;
else {
const unboundedOrder = Math.floor(Math.log10(Math.abs(x)) / 3);
order = Math.max(
0,
minOrder,
Math.min(unboundedOrder, maxOrder, orderSuffixes.length - 1)
);
}
const orderSuffix = orderSuffixes[order];
if (order !== 0)
x /= Math.pow(10, order * 3);
return (style === '$' ? '$' : '') +
x.toLocaleString(
'en-US',
{
style: 'decimal',
minimumFractionDigits: decimals,
maximumFractionDigits: decimals
}
) +
orderSuffix +
(style === '%' ? '%' : '');
}