Modern Tz ZonedDateTime ToIsoString

Home › Time Zones › Time Zones (std/tz) › ZonedDateTime.ToIsoString

ZonedDateTime.ToIsoString

Writes the value as ISO 8601 text with the zone in brackets, which reads back exactly.

Syntax

ZonedDateTime.ToIsoString( ) as ustring

Notes

• The offset has seconds only when they are not zero (+00:19:32), so a present-day value is plain RFC 3339 before the brackets.
• UTC writes +00:00[UTC]. A zone with no id writes no brackets, and that text does not read back as a ZonedDateTime.

Examples

#import "std/tz"
#import "std/tzdata"
#import "std/chrono"
using tz
dim as ZonedDateTime z = ZonedDateTime.FromInstant( chrono.Instant.ParseIso( "2025-07-04T16:00:00Z" ), TimeZone.FindById( "America/New_York" ) )
print z.ToIsoString( )      '' 2025-07-04T12:00:00-04:00[America/New_York]

---

Library: Time Zones (std/tz)
Category: Time Zones
Documented under: ZonedDateTime