This feature is not Baseline because it does not work in some of the most widely-used browsers.
The toJSON() method of Temporal.Duration instances returns a string representing this duration in the same ISO 8601 format as calling toString(). It is intended to be implicitly called by JSON.stringify().
toJSON()
None.
A string representing the given duration in the ISO 8601 format, with as much subsecond precision as necessary to represent the duration accurately.
The toJSON() method is automatically called by JSON.stringify() when a Temporal.Duration object is stringified. This method is generally intended to, by default, usefully serialize Temporal.Duration objects during JSON serialization, which can then be deserialized using the Temporal.Duration.from() function as the reviver of JSON.parse().
const duration = Temporal.Duration.from({ hours: 1, minutes: 30, seconds: 15 });
const durationStr = duration.toJSON(); // 'PT1H30M15S'
const d2 = Temporal.Duration.from(durationStr);
This example shows how Temporal.Duration can be serialized as JSON without extra effort, and how to parse it back.
const duration = Temporal.Duration.from({ hours: 1, minutes: 30, seconds: 15 });
const jsonStr = JSON.stringify({ data: duration }); // '{"data":"PT1H30M15S"}'
const obj = JSON.parse(jsonStr, (key, value) => {
if (key === "data") {
return Temporal.Duration.from(value);
}
return value;
});
| Specification |
|---|
| Temporal> # sec-temporal.duration.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/Duration/toJSON