# ValidationEventHandler

Namespace: **Wisej.Web**

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

Represents the method that will handle the [Validating](/api/wisej.web/extenders/validation.md#validating) event.

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

```csharp
public delegate void ValidationEventHandler(Object sender, ValidationEventArgs e)
```

{% endtab %}

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

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

{% endtab %}
{% endtabs %}

## Parameters

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

## Fired By

| Name                                                                       | Description                                                                                                                              |
| -------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| [Validation.Validating](/api/wisej.web/extenders/validation.md#validating) | Fired when the any control associated to the [Validation](/api/wisej.web/extenders/validation.md) extender is being validated.           |
| [Validation.Validated](/api/wisej.web/extenders/validation.md#validated)   | Fired after any control associated to the [Validation](/api/wisej.web/extenders/validation.md) extender has been successfully validated. |


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