# AddDropHandler

> Allow override of the default behavior for the corresponding window. Multiple handlers can be registered on the same window. If a handler returns DragAndDropVisualMode.None the system will check the next handler. Any other results ( DragAndDropVisualMode.Rejected or others DragAndDropVisualMode ) means this handler has processed the drop event and no other handler will be called. The last handler is the default Unity handler.

## Definition

* **Type:** Method
* **Namespace:** [UnityEditor](/engine/6000.6/script-reference/unityeditor.md)
* **Assembly:** UnityEditor.CoreModule

## AddDropHandler(ProjectBrowserDropHandler)

Allow override of the default behavior for the corresponding window. Multiple handlers can be registered on the same window. If a handler returns [DragAndDropVisualMode.None](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/none.md) the system will check the next handler. Any other results ([DragAndDropVisualMode.Rejected](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/rejected.md) or others [DragAndDropVisualMode](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode.md)) means this handler has processed the drop event and no other handler will be called. The last handler is the default Unity handler.

> **Warning:**
>
> **Removed.** Use AddDropHandlerV2 instead

```csharp
public static void AddDropHandler(DragAndDrop.ProjectBrowserDropHandler handler)
```

### Parameters

**** (\[ProjectBrowserDropHandler]\(/engine/6000.6/script-reference/unityeditor/draganddrop/projectbrowserdrophandler)): Function to handle drop on the corresponding window.

## AddDropHandler(SceneDropHandler)

Allow override of the default behavior for the corresponding window. Multiple handlers can be registered on the same window. If a handler returns [DragAndDropVisualMode.None](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/none.md) the system will check the next handler. Any other results ([DragAndDropVisualMode.Rejected](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/rejected.md) or others [DragAndDropVisualMode](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode.md)) means this handler has processed the drop event and no other handler will be called. The last handler is the default Unity handler.

> **Warning:**
>
> **Removed.** Use AddDropHandlerV2 instead
>
> **Upgrade to** [DragAndDrop.AddDropHandlerV2](/engine/6000.6/script-reference/unityeditor/draganddrop/adddrophandlerv2.md)

```csharp
public static void AddDropHandler(DragAndDrop.SceneDropHandler handler)
```

### Parameters

**** (\[SceneDropHandler]\(/engine/6000.6/script-reference/unityeditor/draganddrop/scenedrophandler)): Function to handle drop on the corresponding window.

## AddDropHandler(HierarchyDropHandler)

Allow override of the default behavior for the corresponding window. Multiple handlers can be registered on the same window. If a handler returns [DragAndDropVisualMode.None](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/none.md) the system will check the next handler. Any other results ([DragAndDropVisualMode.Rejected](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/rejected.md) or others [DragAndDropVisualMode](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode.md)) means this handler has processed the drop event and no other handler will be called. The last handler is the default Unity handler.

> **Warning:**
>
> **Removed.** Use AddDropHandlerV2 instead

```csharp
public static void AddDropHandler(DragAndDrop.HierarchyDropHandler handler)
```

### Parameters

**** (\[HierarchyDropHandler]\(/engine/6000.6/script-reference/unityeditor/draganddrop/hierarchydrophandler)): Function to handle drop on the corresponding window.

## AddDropHandler(InspectorDropHandler)

Allow override of the default behavior for the corresponding window. Multiple handlers can be registered on the same window. If a handler returns [DragAndDropVisualMode.None](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/none.md) the system will check the next handler. Any other results ([DragAndDropVisualMode.Rejected](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode/rejected.md) or others [DragAndDropVisualMode](/engine/6000.6/script-reference/unityeditor/draganddropvisualmode.md)) means this handler has processed the drop event and no other handler will be called. The last handler is the default Unity handler.

> **Warning:**
>
> **Removed.** Use AddDropHandlerV2 instead
>
> **Upgrade to** [DragAndDrop.AddDropHandlerV2](/engine/6000.6/script-reference/unityeditor/draganddrop/adddrophandlerv2.md)

```csharp
public static void AddDropHandler(DragAndDrop.InspectorDropHandler handler)
```

### Parameters

**** (\[InspectorDropHandler]\(/engine/6000.6/script-reference/unityeditor/draganddrop/inspectordrophandler)): Function to handle drop on the corresponding window.