---
title: identifier
framework: appkit
role: symbol
role_heading: Instance Property
path: appkit/nsstoryboardsegue/identifier-swift.property
---

# identifier

An optional, unique identifier for the storyboard segue that you can specify using the Identity inspector in Interface Builder.

## Declaration

```swift
var identifier: NSStoryboardSegue.Identifier? { get }
```

## Discussion

Discussion You use this property if you override the prepare(for:sender:) method of the NSSeguePerforming protocol.

## See Also

### Inspecting a Storyboard Segue

- [sourceController](appkit/nsstoryboardsegue/sourcecontroller.md)
- [destinationController](appkit/nsstoryboardsegue/destinationcontroller.md)
- [NSStoryboardSegue.Identifier](appkit/nsstoryboardsegue/identifier-swift.typealias.md)