JS Intl.DateTimeFormat resolvedOptions()
The Intl.DateTimeFormat.prototype.resolvedOptions() method returns a new object with properties reflecting the locale and date and time formatting options computed during initialization of this DateTimeFormat object.
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Syntax
dateTimeFormat.resolvedOptions()
Return value
A new object with properties reflecting the locale and date and time formatting options computed during the initialization of the given DateTimeFormat object.
Description
The resulting object has the following properties:
locale
The BCP 47 language tag for the locale actually used. If any Unicode extension values were requested in the input BCP 47 language tag that led to this locale, the key-value pairs that were requested and are supported for this locale are included in locale.
calendar
E.g. “gregory”
numberingSystem
The values requested using the Unicode extension keys "ca" and "nu" or filled in as default values.
timeZone
The value provided for this property in the options argument; undefined (representing the runtime’s default time zone) if none was provided. Warning: Applications should not rely on undefined being returned, as future versions may return a String value identifying the runtime’s default time zone instead.
hour12
The value provided for this property in the options argument or filled in as a default.
weekday
era
year
month
day
hour
minute
second
timeZoneName
The values resulting from format matching between the corresponding properties in the options argument and the available combinations and representations for date-time formatting in the selected locale. Some of these properties may not be present, indicating that the corresponding components will not be represented in formatted output.
Examples
Using the resolvedOptions method
var germanFakeRegion = new Intl.DateTimeFormat('de-XX', { timeZone: 'UTC' });
var usedOptions = germanFakeRegion.resolvedOptions();
usedOptions.locale; // "de"
usedOptions.calendar; // "gregory"
usedOptions.numberingSystem; // "latn"
usedOptions.timeZone; // "UTC"
usedOptions.month; // "numeric"
Specifications
| Specification | Status | Comment |
|---|---|---|
| [ECMAScript Internationalization API 1.0 (ECMA-402) | ||
| The definition of ‘Intl.DateTimeFormat.prototype.resolvedOptions’ in that specification.](https://www.ecma-international.org/ecma-402/1.0/#sec-12.3.3) | Standard | Initial definition. |
| [ECMAScript Internationalization API 2.0 (ECMA-402) | ||
| The definition of ‘Intl.DateTimeFormat.prototype.resolvedOptions’ in that specification.](https://www.ecma-international.org/ecma-402/2.0/#sec-Intl.DateTimeFormat.prototype.resolvedOptions) | Standard | |
| [ECMAScript Internationalization API 4.0 (ECMA-402) | ||
| The definition of ‘Intl.DateTimeFormat.prototype.resolvedOptions’ in that specification.](https://tc39.es/ecma402/#sec-Intl.DateTimeFormat.prototype.resolvedOptions) | Draft |
