# IEventFilter

Namespace: **Wisej.Core**

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

Defines the event filter interface to use with the [AddEventFilter](/api/wisej.web/general/application.md#addeventfilter-filter) method.

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

```csharp
public interface IEventFilter
```

{% endtab %}

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

```visual-basic
Public Interface IEventFilter
```

{% endtab %}
{% endtabs %}

## Methods

### ![](/files/hsR4ok3152WyAf8J2C1u) PreFilterEvent(e)

Process an event before it is dispatched.

| Parameter | Type                                                        | Description                                                                                                   |
| --------- | ----------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------- |
| **e**     | [WisejEventArgs](/api/wisej.core/general/wisejeventargs.md) | An instance of [WisejEventArgs](/api/wisej.core/general/wisejeventargs.md) containing the data for the event. |

**Returns:** [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean). true to stop the event from being dispatched; false to allow the event to continue to the next filter or control.


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