---
title: "append(contentsOf:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/data/append(contentsof:)-xeqk"
---

# append(contentsOf:)

Appends the bytes in the specified sequence to the end of the data.

## Declaration

```swift
mutating func append(contentsOf elements: some ContiguousBytes & Sequence<UInt8>)
```