---
title: CFXMLExternalID
framework: Core Foundation
role: symbol
role_heading: Structure
path: corefoundation/cfxmlexternalid
---

# CFXMLExternalID

Contains the system and public IDs for an external entity reference.

## Declaration

```swift
struct CFXMLExternalID
```

## Overview

Overview This structure is part of the definition of the CFXMLDocumentTypeInfo, CFXMLNotationInfo, and CFXMLEntityInfo structures.

## Topics

### Initializers

- [init()](corefoundation/cfxmlexternalid/init().md)
- [init(systemID:publicID:)](corefoundation/cfxmlexternalid/init(systemid:publicid:).md)

### Instance Properties

- [publicID](corefoundation/cfxmlexternalid/publicid.md)
- [systemID](corefoundation/cfxmlexternalid/systemid.md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)

## See Also

### Data Types

- [CFXMLAttributeDeclarationInfo](corefoundation/cfxmlattributedeclarationinfo.md)
- [CFXMLAttributeListDeclarationInfo](corefoundation/cfxmlattributelistdeclarationinfo.md)
- [CFXMLDocumentInfo](corefoundation/cfxmldocumentinfo.md)
- [CFXMLDocumentTypeInfo](corefoundation/cfxmldocumenttypeinfo.md)
- [CFXMLElementInfo](corefoundation/cfxmlelementinfo.md)
- [CFXMLElementTypeDeclarationInfo](corefoundation/cfxmlelementtypedeclarationinfo.md)
- [CFXMLEntityInfo](corefoundation/cfxmlentityinfo.md)
- [CFXMLEntityReferenceInfo](corefoundation/cfxmlentityreferenceinfo.md)
- [CFXMLNotationInfo](corefoundation/cfxmlnotationinfo.md)
- [CFXMLProcessingInstructionInfo](corefoundation/cfxmlprocessinginstructioninfo.md)