//[doc-seo]
{
    "Description": "Use ABP's MVC JavaScript Clock API for time-zone detection, date normalization, localized display, and the browser time-zone cookie."
}

ASP.NET Core MVC / Razor Pages UI: JavaScript Clock API

The abp.clock namespace provides date, time-zone and browser-time-zone helpers for MVC / Razor Pages applications. The application configuration script sets abp.clock.kind from the server-side ABP clock configuration.

Time-Zone Support

abp.clock.supportsMultipleTimezone() returns true when the configured clock kind is Utc. abp.clock.timeZone() returns the value of the Abp.Timing.TimeZone setting when it is available and otherwise returns the browser's IANA time-zone name.

if (abp.clock.supportsMultipleTimezone()) {
    console.log(abp.clock.timeZone());
}

Normalize Date Values

Use normalizeToString before sending a date value to the server and normalizeToLocaleString before displaying a server value:

const requestValue = abp.clock.normalizeToString(new Date());
const displayValue = abp.clock.normalizeToLocaleString(requestValue);

normalizeToString returns an ISO-compatible date-time string. For a non-UTC clock, the core implementation uses yyyy-MM-ddTHH:mm:ss. Both normalization methods return empty or invalid values unchanged.

The standard shared MVC theme bundle loads Luxon and replaces the core implementations of normalizeToString and normalizeToLocaleString. When multiple time zones are supported, this Luxon implementation interprets the input in the configured IANA time zone, converts it to UTC and returns an ISO value ending in Z. The output can include milliseconds (for example, 2026-07-17T08:30:00.000Z), so do not require an exact string length when consuming it.

If an application uses the core scripts without the shared theme's Luxon contributor, the fallback implementation produces a Z-suffixed transport value by detecting the numeric offset of the configured time zone (the abp.clock.timeZone() value, which falls back to the browser time zone). It is not a full IANA time-zone conversion and does not account for fractional-hour offsets or an offset change between the current date and the input date. Include the Luxon contributor when those cases must be handled.

normalizeToLocaleString accepts standard Intl.DateTimeFormat options. When no options are supplied, it uses abp.clock.toLocaleStringOptions. The default options include the numeric year, long month, numeric day, hour, minute and second. You can replace them to define application-wide display defaults:

abp.clock.toLocaleStringOptions = {
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit'
};

Browser Time-Zone Cookie

After application configuration is initialized, ABP writes the browser's time-zone name to the __timezone cookie when multiple time zones are supported. Set the following flag before configuration initialization to disable this behavior:

abp.clock.trySetBrowserTimeZoneToCookie = false;

Use abp.clock.browserTimeZone() to read the browser time zone or abp.clock.setBrowserTimeZoneToCookie() to refresh the cookie explicitly.