# id

> The id of the item being expanded or collapsed. Returns -1 when expandAll() or collapseAll() is being called.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine.UIElements](/engine/6000.5/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
public int id { get; set; }
```