# TreeViewEventHandler

Namespace: **Wisej.Web**

Assembly: **Wisej.Framework** (4.0.0.0)

Represents the method that will handle the [AfterCheck](/api/wisej.web/lists-and-grids/treeview.md#aftercheck), [AfterCollapse](/api/wisej.web/lists-and-grids/treeview.md#aftercollapse), [AfterExpand](/api/wisej.web/lists-and-grids/treeview.md#afterexpand), or [AfterSelect](/api/wisej.web/lists-and-grids/treeview.md#afterselect) event of a [TreeView](/api/wisej.web/lists-and-grids/treeview.md).

{% tabs %}
{% tab title="C#" %}

```csharp
public delegate void TreeViewEventHandler(Object sender, TreeViewEventArgs e)
```

{% endtab %}

{% tab title="VB.NET" %}

```visual-basic
Public Delegate Sub TreeViewEventHandler(ByVal sender As [Object], ByVal e As TreeViewEventArgs)
```

{% endtab %}
{% endtabs %}

## Parameters

| Name       | Type                                                                                        | Description                                                                                                                 |
| ---------- | ------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------- |
| **sender** | [Object](https://docs.microsoft.com/dotnet/api/system.object)                               | The source of the event.                                                                                                    |
| **e**      | [TreeViewEventArgs](/api/wisej.web/lists-and-grids/treeview/wisej.web.treevieweventargs.md) | A [TreeViewEventArgs](/api/wisej.web/lists-and-grids/treeview/wisej.web.treevieweventargs.md) that contains the event data. |

## Fired By

| Name                                                                                                  | Description                                      |
| ----------------------------------------------------------------------------------------------------- | ------------------------------------------------ |
| [TreeNode.AfterCheck](/api/wisej.web/lists-and-grids/treeview/wisej.web.treenode.md#aftercheck)       | Occurs after the tree node check box is checked. |
| [TreeNode.AfterCollapse](/api/wisej.web/lists-and-grids/treeview/wisej.web.treenode.md#aftercollapse) | Occurs after the tree node is collapsed.         |
| [TreeNode.AfterExpand](/api/wisej.web/lists-and-grids/treeview/wisej.web.treenode.md#afterexpand)     | Occurs after the tree node is expanded.          |
| [TreeNode.AfterSelect](/api/wisej.web/lists-and-grids/treeview/wisej.web.treenode.md#afterselect)     | Occurs after the tree node is selected.          |
| [TreeView.AfterCheck](/api/wisej.web/lists-and-grids/treeview.md#aftercheck)                          | Occurs after the tree node check box is checked. |
| [TreeView.AfterCollapse](/api/wisej.web/lists-and-grids/treeview.md#aftercollapse)                    | Occurs after the tree node is collapsed.         |
| [TreeView.AfterExpand](/api/wisej.web/lists-and-grids/treeview.md#afterexpand)                        | Occurs after the tree node is expanded.          |
| [TreeView.AfterSelect](/api/wisej.web/lists-and-grids/treeview.md#afterselect)                        | Occurs after the tree node is selected.          |


---

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