# PhysicsCallbacks.TriggerCallbackTargets.TriggerBeginTarget

> Trigger begin event target for callbacks.

## Definition

* **Type:** Struct
* **Namespace:** [Unity.U2D.Physics](/engine/6000.7/script-reference/unity/u2d/physics.md)
* **Assembly:** UnityEngine.PhysicsCore2DModule
* **Implements:** [IEquatable\<TriggerBeginTarget>](https://learn.microsoft.com/dotnet/api/system.iequatable-1)

```csharp
public readonly struct PhysicsCallbacks.TriggerCallbackTargets.TriggerBeginTarget : IEquatable<PhysicsCallbacks.TriggerCallbackTargets.TriggerBeginTarget>
```

## Properties

| Property                                                                                                                                                | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| ------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [beginEvent](/engine/6000.7/script-reference/unity/u2d/physics/physicscallbacks/triggercallbacktargetstriggerbegintarget/beginevent.md)                 | The trigger begin event.                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [triggerShapeTarget](/engine/6000.7/script-reference/unity/u2d/physics/physicscallbacks/triggercallbacktargetstriggerbegintarget/triggershapetarget.md) | The callback target ([\_callbackTarget](/engine/6000.7/script-reference/unity/u2d/physics/physicsshape/callbacktarget.md)) associated with [\_triggerShape](/engine/6000.7/script-reference/unity/u2d/physics/physicsevents/triggerbeginevent/triggershape.md). This returns any implemented [PhysicsCallbacks.ITriggerCallback](/engine/6000.7/script-reference/unity/u2d/physics/physicscallbacks/itriggercallback.md) or NULL if not implemented or no target. |
| [visitorShapeTarget](/engine/6000.7/script-reference/unity/u2d/physics/physicscallbacks/triggercallbacktargetstriggerbegintarget/visitorshapetarget.md) | The callback target ([\_callbackTarget](/engine/6000.7/script-reference/unity/u2d/physics/physicsshape/callbacktarget.md)) associated with [\_visitorShape](/engine/6000.7/script-reference/unity/u2d/physics/physicsevents/triggerbeginevent/visitorshape.md). This returns any implemented [PhysicsCallbacks.ITriggerCallback](/engine/6000.7/script-reference/unity/u2d/physics/physicscallbacks/itriggercallback.md) or NULL if not implemented or no target. |