# HandleMouseDown(MouseDownEvent)

> Handle mouse down event.

## Definition

* **Type:** Method
* **Namespace:** [UnityEditor.Experimental.GraphView](/engine/6000.5/script-reference/unityeditor/experimental/graphview.md)
* **Assembly:** UnityEditor

```csharp
public abstract bool HandleMouseDown(MouseDownEvent evt)
```

### Parameters

**** (\[MouseDownEvent]\(/engine/6000.5/script-reference/unityengine/uielements/mousedownevent)): The event.

### Returns

| Type                                                          | Description                                         |
| ------------------------------------------------------------- | --------------------------------------------------- |
| [bool](https://learn.microsoft.com/dotnet/api/system.boolean) | True if the drag has been started. False otherwise. |