This parameter MUST be specified on the "DTSTART", "DTEND", "DUE", "EXDATE", and "RDATE" properties when either a DATE-TIME or TIME value type is specified and when the value is neither a UTC or a "floating" time.
The "TZID" property parameter MUST NOT be applied to DATE properties and DATE-TIME or TIME properties whose time values are specified in UTC.
The use of local time in a DATE-TIME or TIME value without the "TZID" property parameter is to be interpreted as floating time, regardless of the existence of "VTIMEZONE" calendar components in the iCalendar object.
Examples of this property parameter:
DTSTART;TZID=America/New_York:19980119T020000
DTEND;TZID=America/New_York:19980119T030000
The "DATE-TIME" value type expresses time values in three forms:
January 18, 1998, at 11 PM:
19980118T230000
January 19, 1998, at 0700 UTC:
19980119T070000Z
2:00 A.M. in New York on January 19, 1998:
TZID=America/New_York:19980119T020000
- dtstamp
- uid
- dtstart
- class
- created
- description
- geo
- last-mod
- location
- organizer
- priority
- seq
- status
- summary
- transp
- url
- recurid
Either 'dtend' or 'duration' MAY appear in a 'eventprop', but 'dtend' and 'duration' MUST NOT occur in the same 'eventprop'.
- dtend
- duration
The following are OPTIONAL, and MAY occur more than once.
- attach
- attendee
- categories
- comment
- contact
- exdate
- rstatus
- related
- resources
- rdate
- x-prop
- iana-prop
- Property Name:
DTSTART
- Value Type: The default value type is DATE-TIME. The time value MUST be one of the forms defined for the DATE-TIME value type. The value type can be set to a DATE value type.
3.8.2.2. Date-Time End