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# set(_:forKey:)

Sets the value of the specified key to a property list object.

```
func set(_ value: Any?, forKey defaultName: String)
```

## Parameters

`value`

The property-list type to store in the defaults database. If you specify an
array or dictionary type, those collections must similarly contain only property list types.

`defaultName`

The key that contains the setting’s name.

## Discussion

Use this method to write property list object types to the defaults store. To store types
that aren’t property list objects, archive them to a [`Data`](/documentation/Foundation/Data)
object and use this method to save that data object to the defaults store.

After you call this method, the system generates a [`didChangeNotification`](/documentation/Foundation/UserDefaults/didChangeNotification)
for registered observers.

---

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