---
title: String.UTF16View
framework: swift
role: symbol
role_heading: Structure
path: swift/string/utf16view
---

# String.UTF16View

A view of a string’s contents as a collection of UTF-16 code units.

## Declaration

```swift
@frozen struct UTF16View
```

## Overview

Overview You can access a string’s view of UTF-16 code units by using its utf16 property. A string’s UTF-16 view encodes the string’s Unicode scalar values as 16-bit integers. let flowers = "Flowers 💐" for v in flowers.utf16 {     print(v) } // 70 // 108 // 111 // 119 // 101 // 114 // 115 // 32 // 55357 // 56464 Unicode scalar values that make up a string’s contents can be up to 21 bits long. The longer scalar values may need two UInt16 values for storage. Those “pairs” of code units are called surrogate pairs. let flowermoji = "💐" for v in flowermoji.unicodeScalars {     print(v, v.value) } // 💐 128144

for v in flowermoji.utf16 {     print(v) } // 55357 // 56464 To convert a String.UTF16View instance back into a string, use the String type’s init(_:) initializer. let favemoji = "My favorite emoji is 🎉" if let i = favemoji.utf16.firstIndex(where: { $0 >= 128 }) {     let asciiPrefix = String(favemoji.utf16[..<i])!     print(asciiPrefix) } // Prints "My favorite emoji is " UTF16View Elements Match NSString Characters The UTF-16 code units of a string’s utf16 view match the elements accessed through indexed NSString APIs. print(flowers.utf16.count) // Prints "10"

let nsflowers = flowers as NSString print(nsflowers.length) // Prints "10" Unlike NSString, however, String.UTF16View does not use integer indices. If you need to access a specific position in a UTF-16 view, use Swift’s index manipulation methods. The following example accesses the fourth code unit in both the flowers and nsflowers strings: print(nsflowers.character(at: 3)) // Prints "119"

let i = flowers.utf16.index(flowers.utf16.startIndex, offsetBy: 3) print(flowers.utf16[i]) // Prints "119" Although the Swift overlay updates many Objective-C methods to return native Swift indices and index ranges, some still return instances of NSRange. To convert an NSRange instance to a range of String.Index, use the Range(_:in:) initializer, which takes an NSRange and a string as arguments. let snowy = "❄️ Let it snow! ☃️" let nsrange = NSRange(location: 3, length: 12) if let range = Range(nsrange, in: snowy) {     print(snowy[range]) } // Prints "Let it snow!"

## Topics

### Instance Properties

- [customPlaygroundQuickLook](swift/string/utf16view/customplaygroundquicklook.md)

### Instance Methods

- [isTriviallyIdentical(to:)](swift/string/utf16view/istriviallyidentical(to:).md)

### Default Implementations

- [BidirectionalCollection Implementations](swift/string/utf16view/bidirectionalcollection-implementations.md)
- [Collection Implementations](swift/string/utf16view/collection-implementations.md)
- [CustomDebugStringConvertible Implementations](swift/string/utf16view/customdebugstringconvertible-implementations.md)
- [CustomReflectable Implementations](swift/string/utf16view/customreflectable-implementations.md)
- [CustomStringConvertible Implementations](swift/string/utf16view/customstringconvertible-implementations.md)
- [Sequence Implementations](swift/string/utf16view/sequence-implementations.md)

## Relationships

### Conforms To

- [BidirectionalCollection](swift/bidirectionalcollection.md)
- [Collection](swift/collection.md)
- [Copyable](swift/copyable.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomReflectable](swift/customreflectable.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Escapable](swift/escapable.md)
- [Sendable](swift/sendable.md)
- [SendableMetatype](swift/sendablemetatype.md)
- [Sequence](swift/sequence.md)

## See Also

### Related String Types

- [Substring](swift/substring.md)
- [StringProtocol](swift/stringprotocol.md)
- [String.Index](swift/string/index.md)
- [String.UnicodeScalarView](swift/string/unicodescalarview.md)
- [String.UTF8View](swift/string/utf8view.md)
- [String.Iterator](swift/string/iterator.md)
- [String.Encoding](swift/string/encoding.md)