Comment en Convertir Timestamps

问题

You avoir un timestamp en one formater (e.g., Unix epoch) et besoin it en another (e.g., ISO 8601 ou local time).

Prérequis

• Understanding of Unix timestamps
• Knowledge of ISO 8601 format

Étapes

1. 1. Identify the input format

   Determine whether the timestamp is a Unix epoch (seconds or milliseconds since 1970-01-01), an ISO 8601 string, or a custom format. Unix timestamps in seconds are 10 digits; milliseconds are 13 digits. This distinction is critical.

   entrée

   1697254800 (seconds)

   输出

   Unix epoch in seconds

2. 2. Convert to the target format

   Parse the timestamp into a date object, then format it as needed. For ISO 8601, use toISOString(). For human-readable, use locale-aware formatting. For Unix timestamp, use getTime()/1000 (seconds) or getTime() (milliseconds).

   entrée

   1697254800 → ISO 8601

   输出

   2023-10-14T03:00:00.000Z

3. 3. Handle timezones correctly

   Unix timestamps are always UTC. When displaying in local time, convert explicitly. Beware of the system's local timezone affecting parsing of date strings. Always store and transmit timestamps in UTC to avoid ambiguity.

   entrée

   UTC → local time

   输出

   timezone-aware display

Résultat attendu

Le timestamp converted en le desired formater, avec timezone handling correct.

Erreurs courantes

Confusing seconds and milliseconds

Unix timestamps can be in seconds (10 digits) or milliseconds (13 digits). Check the magnitude and convert accordingly. JavaScript uses milliseconds.

Timezone offset applied incorrectly

Always work in UTC internally and convert to local time only for display. Use explicit timezone libraries for reliable conversion.

Dépannage指引

• If the date is off by hours, check for a timezone mismatch between the source and your system.
• If the year is 1970, the timestamp was treated as 0 or parsed incorrectly.

Limites de sécurité

• Timestamp conversion is a pure calculation with no security implications.