---
title: "readAttributeNullableCharString(completion:)"
framework: matter
role: symbol
role_heading: Instance Method
path: "matter/mtrbaseclusterunittesting/readattributenullablecharstring(completion:)"
---

# readAttributeNullableCharString(completion:)

## Declaration

```swift
func readAttributeNullableCharString(completion: @escaping @Sendable (String?, (any Error)?) -> Void)
```

```swift
func readAttributeNullableCharString() async throws -> String
```