---
title: "removeObserver(_:forKeyPath:context:)"
framework: foundation
role: symbol
role_heading: Instance Method
path: "foundation/nsorderedset/removeobserver(_:forkeypath:context:)"
---

# removeObserver(_:forKeyPath:context:)

Raises an exception.

## Declaration

```swift
func removeObserver(_ observer: NSObject, forKeyPath keyPath: String, context: UnsafeMutableRawPointer?)
```

## Parameters

- `observer`: The object to remove as an observer.
- `keyPath`: A key-path, relative to the set, for which observer is registered to receive KVO change notifications. This value must not be nil.
- `context`: The context passed to the notifications.

## Discussion

Discussion NSOrderedSet objects are not observable, so this method raises an exception when invoked on an NSOrderedSet object. Instead of observing an ordered set, observe the to-many relationship for which the ordered set is the collection of related objects.

## See Also

### Key-Value Observing Support

- [addObserver(_:forKeyPath:options:context:)](foundation/nsorderedset/addobserver(_:forkeypath:options:context:).md)
- [removeObserver(_:forKeyPath:)](foundation/nsorderedset/removeobserver(_:forkeypath:).md)