---
title: observationInfo
framework: objectivec
role: symbol
role_heading: Instance Property
path: objectivec/nsobject-swift.class/observationinfo
---

# observationInfo

Returns a pointer that identifies information about all of the observers that are registered with the observed object.

## Declaration

```swift
var observationInfo: UnsafeMutableRawPointer? { get set }
```

## Return Value

Return Value A pointer that identifies information about all of the observers that are registered with the observed object, the options that were used at registration-time, and so on.

## Discussion

Discussion The default implementation of this method retrieves the information from a global dictionary of observed objects keyed by memory addresses. For improved performance, both this property and observationInfo can be overridden to store the opaque data pointer in an instance variable. Overrides of this property must not attempt to send messages to the stored data.

## See Also

### Observing Customization

- [automaticallyNotifiesObservers(forKey:)](objectivec/nsobject-swift.class/automaticallynotifiesobservers(forkey:).md)
- [keyPathsForValuesAffectingValue(forKey:)](objectivec/nsobject-swift.class/keypathsforvaluesaffectingvalue(forkey:).md)
- [NSKeyValueObservingCustomization](foundation/nskeyvalueobservingcustomization.md)