> 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.markup/extensions/wisej.web.markup.icommandsourceextensions.md).

# ICommandSourceExtensions

Namespace: **Wisej.Web.Markup**

Assembly: **Wisej.Framework** (4.1.0.0)

Adds [fluent markup](https://learn.microsoft.com/en-us/dotnet/communitytoolkit/maui/markup/markup) extension methods to the [ICommandSource](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommandsource.md) interface.

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

```csharp
public class ICommandSourceExtensions
```

{% endtab %}

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

```visual-basic
Public Class ICommandSourceExtensions
```

{% endtab %}
{% endtabs %}

## Methods

### ![](/files/kO1NJonWXUyy0yRrTxGp) Command\<TCommandSource>(button, value)

Sets the Command property of the specified [ICommandSource](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommandsource.md).

| Parameter          | Type                                                                                            | Description                                                                                                                                   |
| ------------------ | ----------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------- |
| **TCommandSource** |                                                                                                 | The type of the command source, must implement [ICommandSource](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommandsource.md). |
| **button**         | [TCommandSource](/api/wisej.web.markup/extensions/wisej.web.markup.icommandsourceextensions.md) | The command source for which to set the Command property.                                                                                     |
| **value**          | [ICommand](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommand.md)               | The [ICommand](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommand.md) to associate with the command source.                   |

**Returns:** [TCommandSource](/api/wisej.web.markup/extensions/wisej.web.markup.icommandsourceextensions.md). The modified command source with the updated Command property.

This method allows you to associate a command with the command source, enabling command-based interactions.

```csharp

myCommandSource.Command(new RelayCommand());

```

### ![](/files/kO1NJonWXUyy0yRrTxGp) OnCommandChanged\<TCommandSource>(button, action)

Attaches an event handler for the CommandChanged event of the specified [ICommandSource](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommandsource.md).

| Parameter          | Type                                                                                            | Description                                                                                                                                   |
| ------------------ | ----------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------- |
| **TCommandSource** |                                                                                                 | The type of the command source, must implement [ICommandSource](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.icommandsource.md). |
| **button**         | [TCommandSource](/api/wisej.web.markup/extensions/wisej.web.markup.icommandsourceextensions.md) | The command source to attach the event handler to.                                                                                            |
| **action**         | [Action\<TCommandSource>](https://docs.microsoft.com/dotnet/api/system.action-1)                | An action to execute when the command changes.                                                                                                |

**Returns:** [TCommandSource](/api/wisej.web.markup/extensions/wisej.web.markup.icommandsourceextensions.md). The modified command source with the attached CommandChanged event handler.

This method allows you to execute a custom action whenever the command associated with the command source changes.

```csharp

myCommandSource.OnCommandChanged(cs =>
{
AlertBox.Show("Command changed!");
});

```


---

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