# CheckedListBoxExtensions

Namespace: **Wisej.Web.Markup**

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

Adds [fluent markup](https://learn.microsoft.com/en-us/dotnet/communitytoolkit/maui/markup/markup) extension methods to the [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md) class.

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

```csharp
public class CheckedListBoxExtensions
```

{% endtab %}

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

```visual-basic
Public Class CheckedListBoxExtensions
```

{% endtab %}
{% endtabs %}

## Methods

### ![](/files/lIX317sDtMTZJBi9oSIx) CheckOnClick\<TListBox>(listBox, value)

Sets the CheckOnClick property of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter    | Type                                                                                      | Description                                                                                                             |
| ------------ | ----------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox** |                                                                                           | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**  | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md) | The checked list box for which to set the CheckOnClick property.                                                        |
| **value**    | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                           | A boolean indicating whether items are checked on click.                                                                |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the updated CheckOnClick property.

This method allows you to specify whether items in the list box are checked or unchecked when clicked.

```csharp

myCheckedListBox.CheckOnClick(true);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) CheckStateMember\<TListBox>(listBox, checkStateMember)

Sets the CheckStateMember property of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter            | Type                                                                                      | Description                                                                                                             |
| -------------------- | ----------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox**         |                                                                                           | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**          | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md) | The checked list box for which to set the CheckStateMember property.                                                    |
| **checkStateMember** | [String](https://docs.microsoft.com/dotnet/api/system.string)                             | The property to use as the check state for the list items.                                                              |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the updated CheckStateMember property.

This method allows you to set the property to use as the check state for the list items.

```csharp

myCheckedListBox.CheckStateMember("IsChecked");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) OnAfterItemCheck\<TListBox>(listBox, action)

Attaches an event handler for the AfterItemCheck event of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter    | Type                                                                                           | Description                                                                                                             |
| ------------ | ---------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox** |                                                                                                | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**  | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md)      | The checked list box to attach the event handler to.                                                                    |
| **action**   | [Action\<TListBox, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | An action to execute after an item's checked state changes.                                                             |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the attached AfterItemCheck event handler.

This method allows you to execute a custom action after an item's checked state changes in the list box.

```csharp

myCheckedListBox.OnAfterItemCheck((lb, args) =>
{
AlertBox.Show("Item check state changed post-event!");
});

```

### ![](/files/lIX317sDtMTZJBi9oSIx) OnCheckStateMemberChanged\<TListBox>(listBox, action)

Attaches an event handler for the CheckStateMemberChanged event of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter    | Type                                                                                      | Description                                                                                                             |
| ------------ | ----------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox** |                                                                                           | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**  | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md) | The checked list box to attach the event handler to.                                                                    |
| **action**   | [Action\<TListBox>](https://docs.microsoft.com/dotnet/api/system.action-1)                | An action to execute when the CheckStateMember property changes.                                                        |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the attached CheckStateMemberChanged event handler.

This method allows you to execute a custom action whenever the CheckStateMember property changes in the list box.

```csharp

myCheckedListBox.OnCheckStateMemberChanged(lb =>
{
AlertBox.Show("CheckStateMember property changed!");
});

```

### ![](/files/lIX317sDtMTZJBi9oSIx) OnItemCheck\<TListBox>(listBox, action)

Attaches an event handler for the ItemCheck event of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter    | Type                                                                                           | Description                                                                                                             |
| ------------ | ---------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox** |                                                                                                | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**  | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md)      | The checked list box to attach the event handler to.                                                                    |
| **action**   | [Action\<TListBox, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | An action to execute when an item's checked state changes.                                                              |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the attached ItemCheck event handler.

This method allows you to execute a custom action whenever an item's checked state changes in the list box.

```csharp

myCheckedListBox.OnItemCheck((lb, args) =>
{
AlertBox.Show("Item check state changed!");
});

```

### ![](/files/lIX317sDtMTZJBi9oSIx) Separator\<TListBox>(listBox, separator)

Sets the Separator property of the specified [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md).

| Parameter     | Type                                                                                      | Description                                                                                                             |
| ------------- | ----------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| **TListBox**  |                                                                                           | The type of the checked list box, must inherit from [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md). |
| **listBox**   | [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md) | The checked list box for which to set the Separator property.                                                           |
| **separator** | [String](https://docs.microsoft.com/dotnet/api/system.string)                             | The string to use as a separator for the list items.                                                                    |

**Returns:** [TListBox](/api/wisej.web.markup/extensions/wisej.web.markup.checkedlistboxextensions.md). The modified checked list box with the updated Separator property.

This method allows you to set a custom separator for the list items.

```csharp

myCheckedListBox.Separator(", ");

```


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