---
title: errorDomain
framework: foundation
role: symbol
role_heading: Type Property
path: foundation/netservice/errordomain
---

# errorDomain

This key identifies the originator of the error, which is either the NSNetService object or the mach network layer. For most errors, you should not need the value provided by this key.

## Declaration

```swift
class let errorDomain: String
```

## See Also

### Constants

- [errorCode](foundation/netservice/errorcode-swift.type.property.md)