# ConstructRoot<T>()

> Creates the top-level fields of a single blob asset.

## Definition

* **Type:** Method
* **Namespace:** [Unity.Entities](/engine/7000.0/script-reference/unity/entities.md)
* **Assembly:** UnityEngine.EntitiesModule

```csharp
public ref T ConstructRoot<T>() where T : struct
```

### Returns

| Type | Description                                      |
| ---- | ------------------------------------------------ |
| T    | A reference to the blob data under construction. |

### Remarks

This function allocates memory for the top-level fields of a blob asset and returns a reference to it. Use this root reference to initialize field values and to allocate memory for arrays and structs.