# CheckedListBox

Namespace: **Wisej.Web**

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

* [Control](https://docs.wisej.com/api/wisej.web/general/control)
  * [ListControl](https://docs.wisej.com/api/wisej.web/lists-and-grids/listcontrol)
    * [ListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/listbox)
      * [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox)

Displays a [ListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/listbox) in which a check box is displayed to the left of each item.

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

```csharp
public class CheckedListBox : ListBox
```

{% endtab %}

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

```visual-basic
Public Class CheckedListBox
    Inherits ListBox
```

{% endtab %}
{% endtabs %}

## Constructors

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedListBox()

Initializes a new instance of the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) class.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedListBox(onItemCheck)

Initializes a new instance of the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) class.

| Name            | Type                                                                                         | Description                               |
| --------------- | -------------------------------------------------------------------------------------------- | ----------------------------------------- |
| **onItemCheck** | [Action\<Object, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [ItemCheck](#itemcheck) handler. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedListBox(dataSource, displayMember, valueMember, iconMember, checkStateMember, onItemCheck)

Initializes a new instance of [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) class with the specified settings.

| Name                 | Type                                                                                         | Description                                                                              |
| -------------------- | -------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| **dataSource**       | [Object](https://docs.microsoft.com/dotnet/api/system.object)                                | Initial [DataSource](https://docs.wisej.com/api/wisej.web/listcontrol#datasource).       |
| **displayMember**    | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [DisplayMember](https://docs.wisej.com/api/wisej.web/listcontrol#displaymember). |
| **valueMember**      | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [ValueMember](https://docs.wisej.com/api/wisej.web/listcontrol#valuemember).     |
| **iconMember**       | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [IconMember](https://docs.wisej.com/api/wisej.web/listcontrol#iconmember).       |
| **checkStateMember** | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [CheckStateMember](#checkstatemember).                                           |
| **onItemCheck**      | [Action\<Object, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [ItemCheck](#itemcheck) handler.                                                |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedListBox(location, size, onItemCheck)

Initializes a new instance of the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) class with the specified settings.

| Name            | Type                                                                                         | Description                               |
| --------------- | -------------------------------------------------------------------------------------------- | ----------------------------------------- |
| **location**    | [Point](https://docs.microsoft.com/dotnet/api/system.drawing.point)                          | Initial location.                         |
| **size**        | [Size](https://docs.microsoft.com/dotnet/api/system.drawing.size)                            | Initial size.                             |
| **onItemCheck** | [Action\<Object, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [ItemCheck](#itemcheck) handler. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedListBox(location, size, dataSource, displayMember, valueMember, iconMember, checkStateMember, onItemCheck)

Initializes a new instance of the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) class with the specified settings.

| Name                 | Type                                                                                         | Description                                                                              |
| -------------------- | -------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------- |
| **location**         | [Point](https://docs.microsoft.com/dotnet/api/system.drawing.point)                          | Initial location.                                                                        |
| **size**             | [Size](https://docs.microsoft.com/dotnet/api/system.drawing.size)                            | Initial size.                                                                            |
| **dataSource**       | [Object](https://docs.microsoft.com/dotnet/api/system.object)                                | Initial [DataSource](https://docs.wisej.com/api/wisej.web/listcontrol#datasource).       |
| **displayMember**    | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [DisplayMember](https://docs.wisej.com/api/wisej.web/listcontrol#displaymember). |
| **valueMember**      | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [ValueMember](https://docs.wisej.com/api/wisej.web/listcontrol#valuemember).     |
| **iconMember**       | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [IconMember](https://docs.wisej.com/api/wisej.web/listcontrol#iconmember).       |
| **checkStateMember** | [String](https://docs.microsoft.com/dotnet/api/system.string)                                | Initial [CheckStateMember](#checkstatemember).                                           |
| **onItemCheck**      | [Action\<Object, ItemCheckEventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [ItemCheck](#itemcheck) handler.                                                |

## Properties

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedIndices

[CheckedIndexCollection](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.checkedindexcollection): Collection of checked indexes in the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox).

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckedItems

[CheckedObjectCollection](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.checkedobjectcollection): Collection of checked items in the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox).

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckOnClick

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether list items are checked when they are clicked. The default is to check the item when clicking on the checkbox icon. (Default: `False`)

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckStateMember

[String](https://docs.microsoft.com/dotnet/api/system.string): Returns or sets the property to bind to the [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate) of the items in the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) control. (Default: `""`)

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) Items

[ObjectCollection](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.objectcollection): Returns the collection of items in this [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox).

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) Separator

[String](https://docs.microsoft.com/dotnet/api/system.string): Returns or sets the separator used to concatenate and parse multiple checked values for the [Text](#text) property. (Default: `","`)

## Methods

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) ClearChecked()

Unchecks all items in the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox).

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) CreateItemCollection()

Creates a new instance of the item collection.

**Returns:** [ObjectCollection](https://docs.wisej.com/api/wisej.web/lists-and-grids/listbox/wisej.web.listbox.objectcollection). A [ObjectCollection](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.checkedlistbox.objectcollection) that represents the new item collection.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) GetItemChecked(index)

Returns a value indicating whether the specified item is checked.

| Parameter | Type                                                        | Description            |
| --------- | ----------------------------------------------------------- | ---------------------- |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32) | The index of the item. |

**Returns:** [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean). true if the item is checked; otherwise, false.

**Throws:**

* [ArgumentException](https://docs.microsoft.com/dotnet/api/system.argumentexception) The *index* specified is less than zero; or the *index* specified is greater than or equal to the count of items in the list.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) GetItemCheckState(index)

Returns a value indicating the check state of the current item.

| Parameter | Type                                                        | Description                                        |
| --------- | ----------------------------------------------------------- | -------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32) | The index of the item to get the checked value of. |

**Returns:** [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate). One of the [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate) values.

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The *index* specified is less than zero; or the *index* specified is greater than or equal to the count of items in the list.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) OnAfterItemCheck(e)

Fires the [AfterItemCheck](#afteritemcheck) event.

| Parameter | Type                                                                                                                   | Description                                                                                                                                             |
| --------- | ---------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **e**     | [ItemCheckEventArgs](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventargs) | An [ItemCheckEventArgs](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventargs) that contains the event data. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) OnCheckStateMemberChanged(e)

Fires the [CheckStateMemberChanged](#checkstatememberchanged) event.

| Parameter | Type                                                                | Description                                                                                         |
| --------- | ------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------- |
| **e**     | [EventArgs](https://docs.microsoft.com/dotnet/api/system.eventargs) | A [EventArgs](https://docs.microsoft.com/dotnet/api/system.eventargs) that contains the event data. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) OnItemCheck(e)

Fires the [ItemCheck](#itemcheck) event.

| Parameter | Type                                                                                                                   | Description                                                                                                                                             |
| --------- | ---------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **e**     | [ItemCheckEventArgs](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventargs) | An [ItemCheckEventArgs](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventargs) that contains the event data. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) OnWebEvent(e)

Processes the event from the client.

| Parameter | Type                                                                           | Description      |
| --------- | ------------------------------------------------------------------------------ | ---------------- |
| **e**     | [WisejEventArgs](https://docs.wisej.com/api/wisej.core/general/wisejeventargs) | Event arguments. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) OnWebRender(config)

Renders the client component.

| Parameter  | Type                                                          | Description                   |
| ---------- | ------------------------------------------------------------- | ----------------------------- |
| **config** | [Object](https://docs.microsoft.com/dotnet/api/system.object) | Dynamic configuration object. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) RefreshItem(index)

Refreshes the item contained at the specified location.

| Parameter | Type                                                        | Description                          |
| --------- | ----------------------------------------------------------- | ------------------------------------ |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32) | The location of the item to refresh. |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) RefreshItems()

Reloads all the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) items from the data source.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) SetItemChecked(index, value)

Sets [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate) for the item at the specified index to Checked.

| Parameter | Type                                                            | Description                                        |
| --------- | --------------------------------------------------------------- | -------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)     | The index of the item to set the check state for.  |
| **value** | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean) | true to set the item as checked; otherwise, false. |

**Throws:**

* [ArgumentException](https://docs.microsoft.com/dotnet/api/system.argumentexception) The index specified is less than zero; or the index is greater than the count of items in the list.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) SetItemCheckState(index, value)

Sets the check state of the item at the specified index.

| Parameter | Type                                                                                 | Description                                                                                             |
| --------- | ------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------- |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)                          | The index of the item to set the state for.                                                             |
| **value** | [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate) | One of the [CheckState](https://docs.wisej.com/api/wisej.web/enumerations/wisej.web.checkstate) values. |

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The *index* specified is less than zero; or the *index* is greater than or equal to the count of items in the list.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) SetItemCore(index, value)

Sets the object with the specified index in the derived class.

| Parameter | Type                                                          | Description                    |
| --------- | ------------------------------------------------------------- | ------------------------------ |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)   | The array index of the object. |
| **value** | [Object](https://docs.microsoft.com/dotnet/api/system.object) | The object.                    |

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-9bf7fa01e02f4da0f9ef90d3b049ae43e664919e%2Fprotected.png?alt=media) SetItemsCore(value)

Sets the specified array of objects in a collection in the derived class.

| Parameter | Type                                                                    | Description        |
| --------- | ----------------------------------------------------------------------- | ------------------ |
| **value** | [IList](https://docs.microsoft.com/dotnet/api/system.collections.ilist) | An array of items. |

## Events

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) AfterItemCheck

[ItemCheckEventHandler](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventhandler) Fired after the checked state of an item changes.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) CheckStateMemberChanged

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the [CheckStateMember](#checkstatemember) property changes.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) Click

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the user clicks the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) control.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) ItemCheck

[ItemCheckEventHandler](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox/wisej.web.itemcheckeventhandler) Fired when the checked state of an item changes.

### ![](https://1075938901-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2HvlWXJQMV7DxhGzw7Y1%2Fuploads%2Fgit-blob-2389c55cd19719a73a5ae98e1528c8dc8525cc35%2Finstance.png?alt=media) MouseClick

[MouseEventHandler](https://docs.wisej.com/api/wisej.web/general/control/wisej.web.mouseeventhandler) Fired when the user clicks the [CheckedListBox](https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox) control with the mouse.

## Implements

| Name                                                                                                 | Description                                                                                                                                                                                                                                                       |
| ---------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [IUserData](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.iuserdata)                     | Provides access to the `UserData` and `Tag` properties associated to the component implementing this interface.                                                                                                                                                   |
| [IBindableComponent](https://docs.wisej.com/api/wisej.web/data-binding/wisej.web.ibindablecomponent) | Bindable components implement this interface.                                                                                                                                                                                                                     |
| [IDropTarget](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.idroptarget)                 | Controls that support drag & drop operations implement this interface.                                                                                                                                                                                            |
| [ILabel](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.ilabel)                           | Provides access to the [LabelWrapper](https://docs.wisej.com/api/wisej.web/editors/wisej.web.labelwrapper) associated with the controls that implement this interface.                                                                                            |
| [IReadOnly](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.ireadonly)                     | Provides access to the [ReadOnly](https://docs.wisej.com/api/interfaces/wisej.web.ireadonly#readonly) property for coontrols that support the read-only mode.                                                                                                     |
| [IModified](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.imodified)                     | Provides access to the [Modified](https://docs.wisej.com/api/interfaces/wisej.web.imodified#modified) property and [ModifiedChanged](https://docs.wisej.com/api/interfaces/wisej.web.imodified#modifiedchanged) event for controls that implement this interface. |
| [IValidation](https://docs.wisej.com/api/wisej.web/interfaces/wisej.web.ivalidation)                 | Provides access to the validation events and properties property for controls that support validation.                                                                                                                                                            |
| [IWisejComponent](https://docs.wisej.com/api/wisej.core/interfaces/wisej.core.iwisejcomponent)       | All wisej components implement this interface.                                                                                                                                                                                                                    |
| [IWisejControl](https://docs.wisej.com/api/wisej.core/interfaces/wisej.core.iwisejcontrol)           | All wisej controls derived from the [Control](https://docs.wisej.com/api/wisej.web/general/control) class must implement this interface.                                                                                                                          |
| [IWisejSerializable](https://docs.wisej.com/api/wisej.core/interfaces/wisej.core.iwisejserializable) | Allows an object to serialize itself.                                                                                                                                                                                                                             |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.wisej.com/api/wisej.web/lists-and-grids/checkedlistbox.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.