# EventCallback<TEventType>

> Defines the structure of a callback that can be registered onto an element for an event type

## Definition

* **Type:** Delegate
* **Namespace:** [UnityEngine.UIElements](/engine/6000.0/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
public delegate void EventCallback<in TEventType>(TEventType evt)
```