TypedArray.prototype.toLocaleString()

toLocaleString() 方法返回一个字符串，表明该类型化数组的元素。这些元素被转化为字符串并由一个区域设置指定的分隔符（例如逗号“,”）分隔。这个方法与 Number.prototype.toLocaleString() 是相同的。（类型化数组）的是typed array types中的其中一个。

语法 

typedarray.toLocaleString([locales [, options]]);

参数

locales Optional

A string with a BCP 47 language tag, or an array of such strings. For the general form and interpretation of the locales argument, see the Intl page. The following Unicode extension key is allowed:

nu
The numbering system to be used. Possible values include: "arab" , "arabext" , "bali" , "beng" , "deva" , "fullwide" , "gujr" , "guru" , "hanidec" , "khmr" , "knda" , "laoo" , "latn" , "limb" , "mlym" , "mong" , "mymr" , "orya" , "tamldec" , "telu" , "thai" , "tibt" .
options Optional

An object with some or all of the following properties:

localeMatcher
The locale matching algorithm to use. Possible values are "lookup" and "best fit" ; the default is "best fit" . For information about this option, see the Intl page.
style
The formatting style to use , the default is "decimal" .
  • " decimal " for plain number formatting.
  • " currency " for currency formatting.
  • " percent " for percent formatting
  • " unit " for unit formatting
unit
The unit to use in unit formatting, Possible values are core unit identifiers, defined in UTS #35, Part 2, Section 6. A subset of units from the full list was selected for use in ECMAScript. Pairs of simple units can be concatenated with "-per-" to make a compound unit. There is no default value; if the style is "unit" , the unit property must be provided.
unitDisplay
The unit formatting style to use in unit formatting, the defaults is " short ".
  • " long "(e.g., 16 litres )
  • " short "(e.g., 16 l )
  • " narrow "(e.g., 16l )
currency
The currency to use in currency formatting. Possible values are the ISO 4217 currency codes, such as "USD" for the US dollar, "EUR" for the euro, or "CNY" for the Chinese RMB — see the Current currency & funds code list. There is no default value; if the style is "currency" , the currency property must be provided.
currencyDisplay
How to display the currency in currency formatting. Possible values are "symbol" to use a localized currency symbol such as €, "code" to use the ISO currency code, "name" to use a localized currency name such as "dollar" ; the default is "symbol" .
useGrouping
Whether to use grouping separators, such as thousands separators or thousand/lakh/crore separators. Possible values are true and false ; the default is true .

The following properties fall into two groups: minimumIntegerDigits , minimumFractionDigits , and maximumFractionDigits in one group, minimumSignificantDigits and maximumSignificantDigits in the other. If at least one property from the second group is defined, then the first group is ignored.

minimumIntegerDigits
The minimum number of integer digits to use. Possible values are from 1 to 21; the default is 1.
minimumFractionDigits
The minimum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number and percent formatting is 0; the default for currency formatting is the number of minor unit digits provided by the ISO 4217 currency code list(2 if the list doesn't provide that information).
maximumFractionDigits
The maximum number of fraction digits to use. Possible values are from 0 to 20; the default for plain number formatting is the larger of minimumFractionDigits and 3; the default for currency formatting is the larger of minimumFractionDigits and the number of minor unit digits provided by the ISO 4217 currency code list(2 if the list doesn't provide that information); the default for percent formatting is the larger of minimumFractionDigits and 0.
minimumSignificantDigits
The minimum number of significant digits to use. Possible values are from 1 to 21; the default is 1.
maximumSignificantDigits
The maximum number of significant digits to use. Possible values are from 1 to 21; the default is 21.
notation
The formatting that should be displayed for the number, the defaults is " standard "
  • " standard " plain number formatting
  • " scientific " return the order-of-magnitude for formatted number.
  • " engineering " return the exponent of ten when divisible by three
  • " compact " string representing exponent, defaults is using the "short" form
    • " compactDisplay " used only when notation is "compact", takes either "short"(default)or "long"

返回值

一个字符串，表明该类型化数组内的元素。

例子

使用 toLocaleString 

var uint = new Uint32Array([2000, 500, 8123, 12, 4212]);

uint.toLocaleString(); 
// 如果在de-DE区域设置下运行
// "2.000,500,8.123,12,4.212"

uint.toLocaleString('en-US');
// "2,000,500,8,123,12,4,212"

uint.toLocaleString('ja-JP', { style: 'currency', currency: 'JPY' });
// "￥2,000,￥500,￥8,123,￥12,￥4,212"

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