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# dateSeparator(_:)

Modifies the ISO 8601 date format style to use the specified date separator.

```
func dateSeparator(_ separator: Date.ISO8601FormatStyle.DateSeparator) -> Date.ISO8601FormatStyle
```

## Parameters

`separator`

Character used to separate the year, month, and day in a date.

## Return Value

An ISO 8601 date format style modified to include the specified date separator style.

## Discussion

Possible values of [`Date.ISO8601FormatStyle.DateSeparator`](/documentation/Foundation/Date/ISO8601FormatStyle/DateSeparator-swift.enum) are [`Date.ISO8601FormatStyle.DateSeparator.dash`](/documentation/Foundation/Date/ISO8601FormatStyle/DateSeparator-swift.enum/dash) and [`Date.ISO8601FormatStyle.DateSeparator.omitted`](/documentation/Foundation/Date/ISO8601FormatStyle/DateSeparator-swift.enum/omitted).

The following example shows a variety of [`Date.ISO8601FormatStyle.DateSeparator`](/documentation/Foundation/Date/ISO8601FormatStyle/DateSeparator-swift.enum) formats applied to an ISO 8601 date format.

```swift
let meetingDate = Date() // Jun 23, 2021 at 6:13 AM
meetingDate.formatted(.iso8601.dateSeparator(.omitted)) // 20210623T111325Z
meetingDate.formatted(.iso8601.dateSeparator(.dash)) // 2021-06-23T111325Z
meetingDate.formatted(.iso8601) // 20210623T111325Z
```

If no format is specified as a parameter, the [`Date.ISO8601FormatStyle.DateSeparator.omitted`](/documentation/Foundation/Date/ISO8601FormatStyle/DateSeparator-swift.enum/omitted) case is the default format.

For more information about ISO 8601 formatted dates, see the [`Date.ISO8601FormatStyle`](/documentation/Foundation/Date/ISO8601FormatStyle).

---

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