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

# format(_:)

Formats an integer, using this style.

## Declaration

```swift
func format(_ value: Value) -> String
```

## Parameters

- `value`: The integer to format.

## Return Value

Return Value A string 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 use it to format multiple integers. The following example creates a style that uses the en_US locale, and adds the compactName modifier. It applies this style to all the integers in an array. let compactNameStyle = IntegerFormatStyle<Int>(     locale: Locale(identifier: "en_US"))     .notation(.compactName) let nums = [100, 1000, 10000, 100000, 1000000] let formattedNums = nums.map { compactNameStyle.format($0) } // ["100", "1K", "10K", "100K", "1M"]

To format a single integer, use the BinaryInteger instance method formatted(_:), passing in an instance of IntegerFormatStyle, or formatted() to use a default style.