> For the complete documentation index, see [llms.txt](https://docs.wisej.com/api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wisej.com/api/wisej.web/containers/tabcontrol/wisej.web.tabcontrolcanceleventhandler.md).

# TabControlCancelEventHandler

Namespace: **Wisej.Web**

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

Represents the method that will handle the [Selecting](/api/wisej.web/containers/tabcontrol.md#selecting) or [Deselecting](/api/wisej.web/containers/tabcontrol.md#deselecting) event of a [TabControl](/api/wisej.web/containers/tabcontrol.md) control.

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

```csharp
public delegate void TabControlCancelEventHandler(Object sender, TabControlCancelEventArgs e)
```

{% endtab %}

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

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

{% endtab %}
{% endtabs %}

## Parameters

| Name       | Type                                                                                                     | Description                                                                                                                              |
| ---------- | -------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| **sender** | [Object](https://docs.microsoft.com/dotnet/api/system.object)                                            | The source of the event.                                                                                                                 |
| **e**      | [TabControlCancelEventArgs](/api/wisej.web/containers/tabcontrol/wisej.web.tabcontrolcanceleventargs.md) | A [TabControlCancelEventArgs](/api/wisej.web/containers/tabcontrol/wisej.web.tabcontrolcanceleventargs.md) that contains the event data. |

## Fired By

| Name                                                                          | Description                                                                              |
| ----------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| [TabControl.Selecting](/api/wisej.web/containers/tabcontrol.md#selecting)     | Occurs before a tab is selected, enabling a handler to cancel the tab change.            |
| [TabControl.TabClosing](/api/wisej.web/containers/tabcontrol.md#tabclosing)   | Occurs before a tab is closed by the user, enabling a handler to cancel the tab closing. |
| [TabControl.Deselecting](/api/wisej.web/containers/tabcontrol.md#deselecting) | Occurs before a tab is deselected, enabling a handler to cancel the tab change.          |


---

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