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# time(includingFractionalSeconds:)

Modifies the ISO 8601 date format style to include the time in the formatted output.

```
func time(includingFractionalSeconds: Bool) -> Date.ISO8601FormatStyle
```

## Parameters

`includingFractionalSeconds`

Specifies whether the format style inclues the fractional component of the seconds.

## Return Value

An ISO 8601 date format style modified to include the time.

## Discussion

The following example shows an ISO 8601 format with, and without, a time and fractional seconds.

```swift
let meetingDate = Date() // Jun 24, 2021 at 6:52 AM
meetingDate.formatted(.iso8601
    .year()
    .month()
    .day()
    .time(includingFractionalSeconds: false)
)
// 20210624T115209

meetingDate.formatted(.iso8601
    .year()
    .time(includingFractionalSeconds: true)
)
// 2021T115209.274

meetingDate.formatted(.iso8601
    .year()
    .year()
    .month()
    .day()
    .dateSeparator(.dash)
    .time(includingFractionalSeconds: true)
    .timeSeparator(.colon)
)
// 2021-06-24T11:52:09.274

meetingDate.formatted(.iso8601
    .year()
    .year()
    .month()
    .day()
    .dateSeparator(.dash)
    .time(includingFractionalSeconds: false)
    .timeSeparator(.colon)
    .dateTimeSeparator(.space)
)
// 2021-06-24 11:52:09
```

The default [`Date.ISO8601FormatStyle`](/documentation/Foundation/Date/ISO8601FormatStyle) includes the time but not the fractional seconds.

For more information about formatting dates, see the [`Date.FormatStyle`](/documentation/Foundation/Date/FormatStyle).

---

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