# UxmlAttributeDescription.Use

> An enum to describe attribute use.

## Definition

* **Type:** Enum
* **Namespace:** [UnityEngine.UIElements](/engine/6000.3/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
public enum UxmlAttributeDescription.Use
```

## Fields

| Value                                                                                                           | Description                                                            |
| --------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------- |
| [None](/engine/6000.3/script-reference/unityengine/uielements/uxmlattributedescription/use/none.md)             | There is no restriction on the use of this attribute with the element. |
| [Optional](/engine/6000.3/script-reference/unityengine/uielements/uxmlattributedescription/use/optional.md)     | The attribute is optional for the element.                             |
| [Prohibited](/engine/6000.3/script-reference/unityengine/uielements/uxmlattributedescription/use/prohibited.md) | The attribute should not appear for the element.                       |
| [Required](/engine/6000.3/script-reference/unityengine/uielements/uxmlattributedescription/use/required.md)     | The attribute must appear in the element tag.                          |