---
title: "format(_:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/measurement/formatstyle/bytecount/format(_:)"
---

# format(_:)

Formats a byte count measurment, using this style.

## Declaration

```swift
func format(_ value: Measurement<UnitInformationStorage>) -> String
```

## Parameters

- `value`: The byte count measurement to format.

## Return Value

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

## Discussion

Discussion Use this method when you want to create a single style instance, and then use it to format multiple values. The following example creates a Measurement.FormatStyle.ByteCount instance to format values as kilobyte counts, then applies this style to an array of Measurement values. let style = Measurement.FormatStyle.ByteCount(style: .memory,                                                                                             allowedUnits: [.kb],                                               spellsOutZero: true,                                               includesActualByteCount: false,                                               locale: Locale(identifier: "en_US")) let counts: [Measurement] = [     Measurement(value: 0, unit: UnitInformationStorage.bytes),     Measurement(value: 1024, unit: UnitInformationStorage.bytes),     Measurement(value: 2048, unit: UnitInformationStorage.bytes),     Measurement(value: 4096, unit: UnitInformationStorage.bytes),     Measurement(value: 8192, unit: UnitInformationStorage.bytes),     Measurement(value: 16384, unit: UnitInformationStorage.bytes),     Measurement(value: 32768, unit: UnitInformationStorage.bytes),     Measurement(value: 65536, unit: UnitInformationStorage.bytes) ] let formatted = counts.map ( {style.format($0) } ) // ["Zero kB", "1 kB", "2 kB", "4 kB", "8 kB", "16 kB", "32 kB", "64 kB"] To format a single data-storage measurement, use the Measurement instance method formatted(_:), passing in an instance of Measurement.FormatStyle.ByteCount, or formatted() to use a default style.