---
title: "init(charactersIn:)"
framework: foundation
role: symbol
role_heading: Initializer
path: "foundation/nsmutablecharacterset/init(charactersin:)"
---

# init(charactersIn:)

Returns a character set containing the characters in a given string.

## Declaration

```swift
init(charactersIn aString: String)
```

## See Also

### Creating Custom Character Sets

- [init(range:)](foundation/nsmutablecharacterset/init(range:).md)
- [init(bitmapRepresentation:)](foundation/nsmutablecharacterset/init(bitmaprepresentation:).md)
- [init(contentsOfFile:)](foundation/nsmutablecharacterset/init(contentsoffile:).md)