# EditorApplication.CallbackFunction

> Delegate to be called from EditorApplication callbacks.

## Definition

* **Type:** Delegate
* **Namespace:** [UnityEditor](/engine/6000.0/script-reference/unityeditor.md)
* **Assembly:** UnityEditor

```csharp
public delegate void EditorApplication.CallbackFunction()
```

## Remarks

CallbackFunction is used by [EditorApplication.update](/engine/6000.0/script-reference/unityeditor/editorapplication/update.md), [EditorApplication.modifierKeysChanged](/engine/6000.0/script-reference/unityeditor/editorapplication/modifierkeyschanged.md), playmodeStateChanged, and [EditorApplication.hierarchyWindowChanged](/engine/6000.0/script-reference/unityeditor/editorapplication/hierarchywindowchanged.md).