This feature is not Baseline because it does not work in some of the most widely-used browsers.
The toJSON() method of Temporal.Instant instances returns a string representing this instant in the same RFC 9557 format as calling toString(). It is intended to be implicitly called by JSON.stringify().
toJSON()
None.
A string representing the given instant in the RFC 9557 format, with as much subsecond precision as necessary to represent the duration accurately, and with the UTC time zone designator Z.
The toJSON() method is automatically called by JSON.stringify() when a Temporal.Instant object is stringified. This method is generally intended to, by default, usefully serialize Temporal.Instant objects during JSON serialization, which can then be deserialized using the Temporal.Instant.from() function as the reviver of JSON.parse().
const instant = Temporal.Instant.fromEpochMilliseconds(1627821296000); const instantStr = instant.toJSON(); // '2021-08-01T12:34:56Z' const i2 = Temporal.Instant.from(instantStr);
This example shows how Temporal.Instant can be serialized as JSON without extra effort, and how to parse it back.
const instant = Temporal.Instant.fromEpochMilliseconds(1627821296000);
const jsonStr = JSON.stringify({ time: instant }); // '{"time":"2021-08-01T12:34:56Z"}'
const obj = JSON.parse(jsonStr, (key, value) => {
if (key === "time") {
return Temporal.Instant.from(value);
}
return value;
});
| Specification |
|---|
| Temporal> # sec-temporal.instant.prototype.tojson> |
| Desktop | Mobile | Server | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | Bun | Deno | Node.js | |
toJSON |
144 | 144 | 139 | No | preview | 144 | 139 | No | No | No | 144 | No | ? | 1.40 | No |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Temporal/Instant/toJSON