The Intl.RelativeTimeFormat()
constructor creates Intl.RelativeTimeFormat
objects.
Syntax
new Intl.RelativeTimeFormat([locales[, options]])
Parameters
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. 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. numeric
-
The format of output message. Possible values are:
- "
always
" (default, e.g.,1 day ago
), - or "
auto
" (e.g.,yesterday
). The "auto
" value allows to not always have to use numeric values in the output.
- "
style
-
The length of the internationalized message. Possible values are:
- "
long
" (default, e.g.,in 1 month
) - "
short
" (e.g.,in 1 mo.
), - or "
narrow
" (e.g.,in 1 mo.
). The narrow style could be similar to the short style for some locales.
- "
Examples
Basic format usage
The following example shows how to create a relative time formatter using the English language.
// Create a relative time formatter in your locale
// with default values explicitly passed in.
const rtf = new Intl.RelativeTimeFormat("en", {
localeMatcher: "best fit", // other values: "lookup"
numeric: "always", // other values: "auto"
style: "long", // other values: "short" or "narrow"
});
// Format relative time using negative value (-1).
rtf.format(-1, "day");
// > "1 day ago"
// Format relative time using positive value (1).
rtf.format(1, "day");
// > "in 1 day"
Using the auto option
If numeric:auto
option is passed, it will produce the string yesterday
or tomorrow
instead of 1 day ago
or in 1 day
. This allows to not always have to use numeric values in the output.
// Create a relative time formatter in your locale
// with numeric: "auto" option value passed in.
const rtf = new Intl.RelativeTimeFormat("en", { numeric: "auto" });
// Format relative time using negative value (-1).
rtf.format(-1, "day");
// > "yesterday"
// Format relative time using positive day unit (1).
rtf.format(1, "day");
// > "tomorrow"
Specifications
Specification |
---|
ECMAScript Internationalization API (ECMA-402) The definition of 'RelativeTimeFormat()' in that specification. |
Browser compatibility
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