# Validation3d<T> delegate

Namespace: [Grasshopper.Kernel.Geometry.SpatialTrees](https://developer.rhino3d.com/api/gh1/namespace/grasshopper.kernel.geometry.spatialtrees.md) · Assembly: [Grasshopper](https://developer.rhino3d.com/api/gh1/assembly/grasshopper.md)

```cs
public delegate Validation3d<T>
```

Delegate to be used during advanced customized searches.

**Type parameters:**

- `T`: Element type.

**Signature:**

```cs
bool Validation3d<T>(T element, int globalIndex, Node3d<T> node)
```

**Parameters:**

- `element` (`T`): Potential hit.
- `globalIndex` ([int](https://learn.microsoft.com/dotnet/api/system.int32)): Index of item in global list.
- `node` ([Node3d<T>](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.geometry.spatialtrees.node3d-1.md)): Node containing the element.