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# format(_:)

Formats a numeric byte count, using this style.

```
func format(_ value: Int64) -> AttributedString
```

## Parameters

`value`

The 64-bit byte count to format.

## Return Value

A formatted representation of `value`, formatted according to the style’s configuration.

## Discussion

Use this method when you want to create a single style instance, and then use it to format multiple values. To format a single integer, use the <doc://com.apple.documentation/documentation/Swift/BinaryInteger> instance method <doc://com.apple.documentation/documentation/Swift/BinaryInteger/formatted(_:)-4qd73>, passing in an instance of [`ByteCountFormatStyle.Attributed`](/documentation/Foundation/ByteCountFormatStyle/Attributed-swift.struct), or <doc://com.apple.documentation/documentation/Swift/BinaryInteger/formatted()> to use a default style.

---

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