# ListBox

Namespace: **Wisej.Web**

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

* [Control](/api/wisej.web/general/control.md)
  * [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md)
    * [ListBox](/api/wisej.web/lists-and-grids/listbox.md)

Represents a control to display a list of items.

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

```csharp
public class ListBox : ListControl, ILabel, IReadOnly
```

{% endtab %}

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

```visual-basic
Public Class ListBox
    Inherits ListControl
    Implements ILabel, IReadOnly
```

{% endtab %}
{% endtabs %}

## Constructors

### ![](/files/hsR4ok3152WyAf8J2C1u) ListBox()

Initializes a new instance of [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/hsR4ok3152WyAf8J2C1u) ListBox(onSelectedIndexChanged)

Initializes a new instance of the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) class with the specified settings.

| Name                       | Type                                                                                | Description                                                     |
| -------------------------- | ----------------------------------------------------------------------------------- | --------------------------------------------------------------- |
| **onSelectedIndexChanged** | [Action\<Object, EventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [SelectedIndexChanged](#selectedindexchanged) handler. |

### ![](/files/hsR4ok3152WyAf8J2C1u) ListBox(dataSource, displayMember, valueMember, iconMember, onSelectedIndexChanged)

Initializes a new instance of [ListBox](/api/wisej.web/lists-and-grids/listbox.md) class with the specified settings.

| Name                       | Type                                                                                | Description                                                                           |
| -------------------------- | ----------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- |
| **dataSource**             | [Object](https://docs.microsoft.com/dotnet/api/system.object)                       | Initial [DataSource](/api/wisej.web/lists-and-grids/listcontrol.md#datasource).       |
| **displayMember**          | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [DisplayMember](/api/wisej.web/lists-and-grids/listcontrol.md#displaymember). |
| **valueMember**            | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [ValueMember](/api/wisej.web/lists-and-grids/listcontrol.md#valuemember).     |
| **iconMember**             | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [IconMember](/api/wisej.web/lists-and-grids/listcontrol.md#iconmember).       |
| **onSelectedIndexChanged** | [Action\<Object, EventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [SelectedIndexChanged](#selectedindexchanged) handler.                       |

### ![](/files/hsR4ok3152WyAf8J2C1u) ListBox(location, size, onSelectedIndexChanged)

Initializes a new instance of the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) 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.                                                   |
| **onSelectedIndexChanged** | [Action\<Object, EventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [SelectedIndexChanged](#selectedindexchanged) handler. |

### ![](/files/hsR4ok3152WyAf8J2C1u) ListBox(location, size, dataSource, displayMember, valueMember, iconMember, onSelectedIndexChanged)

Initializes a new instance of the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) 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](/api/wisej.web/lists-and-grids/listcontrol.md#datasource).       |
| **displayMember**          | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [DisplayMember](/api/wisej.web/lists-and-grids/listcontrol.md#displaymember). |
| **valueMember**            | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [ValueMember](/api/wisej.web/lists-and-grids/listcontrol.md#valuemember).     |
| **iconMember**             | [String](https://docs.microsoft.com/dotnet/api/system.string)                       | Initial [IconMember](/api/wisej.web/lists-and-grids/listcontrol.md#iconmember).       |
| **onSelectedIndexChanged** | [Action\<Object, EventArgs>](https://docs.microsoft.com/dotnet/api/system.action-2) | Optional [SelectedIndexChanged](#selectedindexchanged) handler.                       |

## Properties

### ![](/files/hsR4ok3152WyAf8J2C1u) AllowHtml

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets a value indicating that the control can display HTML in the Text property. (Default: `False`)

### ![](/files/lzopMboA31bVq8UIcbT3) AllowSelection

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns a value indicating whether the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) currently enables selection of list items.

### ![](/files/lzopMboA31bVq8UIcbT3) DefaultSize

[Size](https://docs.microsoft.com/dotnet/api/system.drawing.size): Returns the default size for a text box control.

### ![](/files/hsR4ok3152WyAf8J2C1u) HorizontalScrollbar

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether a horizontal scroll bar is displayed in the control. (Default: `False`)

### ![](/files/hsR4ok3152WyAf8J2C1u) IncrementalSelection

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether items are selected incrementally as the user types within a timeout of 1 second. (Default: `True`)

### ![](/files/hsR4ok3152WyAf8J2C1u) ItemHeight

[Int32](https://docs.microsoft.com/dotnet/api/system.int32): Gets or sets the height of the list items. When the value is -1, uses the value set in the theme. (Default: `-1`)

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The assigned value is less than -1; or the assigned value is greater than 500.

### ![](/files/hsR4ok3152WyAf8J2C1u) Items

[ObjectCollection](/api/wisej.web/lists-and-grids/listbox/wisej.web.listbox.objectcollection.md): Returns the collection of the items contained in this [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/hsR4ok3152WyAf8J2C1u) Label

[LabelWrapper](/api/wisej.web/editors/wisej.web.labelwrapper.md): Provides a label related to the control.

### ![](/files/hsR4ok3152WyAf8J2C1u) LabelText

[String](https://docs.microsoft.com/dotnet/api/system.string): Returns or sets the localizable label associated with this control. (Default: `""`)

### ![](/files/hsR4ok3152WyAf8J2C1u) LazyLoading

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether the items in the list are send to the client when the list becomes visible the first time. (Default: `False`)

### ![](/files/hsR4ok3152WyAf8J2C1u) Orientation

[Orientation](/api/wisej.web/enumerations/wisej.web.orientation.md): Returns or sets whether the list box displays the items vertically (default) or horizontally. <mark style="color:blue;background-color:green;">Since 3.1</mark> (Default: `Vertical`)

**Throws:**

* [InvalidOperationException](https://docs.microsoft.com/dotnet/api/system.invalidoperationexception) Horizontal orientation is not supported with virtual scrolling.

### ![](/files/hsR4ok3152WyAf8J2C1u) ReadOnly

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether the control is read-only. (Default: `False`)

### ![](/files/hsR4ok3152WyAf8J2C1u) RightClickSelection

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether the item under the pointer gets selected on a right click. (Default: `False`)

When the right click lands outside of a selected area the selection is not changed regardless of the value of [RightClickSelection](#rightclickselection).

### ![](/files/hsR4ok3152WyAf8J2C1u) ScrollAlwaysVisible

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether the vertical scroll bar is shown at all times. (Default: `False`)

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectedIndex

[Int32](https://docs.microsoft.com/dotnet/api/system.int32): Returns or sets the zero-based index of the currently selected item in a [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The assigned value is less than -1 or greater than or equal to the item count.
* [ArgumentException](https://docs.microsoft.com/dotnet/api/system.argumentexception) The [SelectionMode](#selectionmode) property is set to None.

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectedIndices

[SelectedIndexCollection](/api/wisej.web/lists-and-grids/listbox/wisej.web.listbox.selectedindexcollection.md): Returns a collection that contains the zero-based indexes of all currently selected items in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectedItem

[Object](https://docs.microsoft.com/dotnet/api/system.object): Returns or sets the currently selected item in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectedItems

[SelectedObjectCollection](/api/wisej.web/lists-and-grids/listbox/wisej.web.listbox.selectedobjectcollection.md): Returns a collection containing the currently selected items in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectionMode

[SelectionMode](/api/wisej.web/enumerations/wisej.web.selectionmode.md): Returns or sets the method in which items are selected in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md). (Default: `One`)

### ![](/files/hsR4ok3152WyAf8J2C1u) Sorted

[Boolean](https://docs.microsoft.com/dotnet/api/system.boolean): Returns or sets whether the items in the combo box are sorted. (Default: `False`)

**Throws:**

* [ArgumentException](https://docs.microsoft.com/dotnet/api/system.argumentexception) An attempt was made to sort a [ListBox](/api/wisej.web/lists-and-grids/listbox.md) that is attached to a data source.

### ![](/files/hsR4ok3152WyAf8J2C1u) Tools

[ComponentToolCollection](/api/wisej.web/editors/wisej.web.componenttoolcollection.md): Returns the instance of [ComponentToolCollection](/api/wisej.web/editors/wisej.web.componenttoolcollection.md) associated with this control.

### ![](/files/hsR4ok3152WyAf8J2C1u) TopIndex

[Int32](https://docs.microsoft.com/dotnet/api/system.int32): Returns or sets the index of the first visible item in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

## Methods

### ![](/files/hsR4ok3152WyAf8J2C1u) BeginUpdate()

Not used. Kept for compatibility.

### ![](/files/hsR4ok3152WyAf8J2C1u) ClearSelected()

Unselects all items in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/lzopMboA31bVq8UIcbT3) CreateItemCollection()

Creates a new instance of the item collection.

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

### ![](/files/lzopMboA31bVq8UIcbT3) Dispose(disposing)

Disposes the control.

| Parameter     | Type                                                            | Description                                                                 |
| ------------- | --------------------------------------------------------------- | --------------------------------------------------------------------------- |
| **disposing** | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean) | true when this method is called by the application rather than a finalizer. |

### ![](/files/hsR4ok3152WyAf8J2C1u) EndUpdate()

Not used. Kept for compatibility.

### ![](/files/hsR4ok3152WyAf8J2C1u) FindString(text)

Returns the index of the first item in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) that starts with the specified string.

| Parameter | Type                                                          | Description                                                                      |
| --------- | ------------------------------------------------------------- | -------------------------------------------------------------------------------- |
| **text**  | [String](https://docs.microsoft.com/dotnet/api/system.string) | The [String](https://docs.microsoft.com/dotnet/api/system.string) to search for. |

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The zero-based index of the first item found; returns -1 if no match is found.

### ![](/files/hsR4ok3152WyAf8J2C1u) FindString(text, startIndex)

Returns the index of the first item in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) beyond the specified index that contains the specified string. The search is not case sensitive.

| Parameter      | Type                                                          | Description                                                                                                                   |
| -------------- | ------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| **text**       | [String](https://docs.microsoft.com/dotnet/api/system.string) | The [String](https://docs.microsoft.com/dotnet/api/system.string) to search for.                                              |
| **startIndex** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)   | The zero-based index of the item before the first item to be searched. Set to -1 to search from the beginning of the control. |

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The zero-based index of the first item found; returns -1 if no match is found, or 0 if the *text* parameter specifies [Empty](https://docs.microsoft.com/dotnet/api/system.string.empty).

### ![](/files/hsR4ok3152WyAf8J2C1u) FindStringExact(text)

Finds the first item in the combo box that matches the specified string.

| Parameter | Type                                                          | Description                                                                      |
| --------- | ------------------------------------------------------------- | -------------------------------------------------------------------------------- |
| **text**  | [String](https://docs.microsoft.com/dotnet/api/system.string) | The [String](https://docs.microsoft.com/dotnet/api/system.string) to search for. |

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The zero-based index of the first item found; returns -1 if no match is found, or 0 if the *text* parameter specifies [Empty](https://docs.microsoft.com/dotnet/api/system.string.empty).

### ![](/files/hsR4ok3152WyAf8J2C1u) FindStringExact(text, startIndex)

Finds the first item after the specified index that matches the specified string.

| Parameter      | Type                                                          | Description                                                                                                                   |
| -------------- | ------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| **text**       | [String](https://docs.microsoft.com/dotnet/api/system.string) | The [String](https://docs.microsoft.com/dotnet/api/system.string) to search for.                                              |
| **startIndex** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)   | The zero-based index of the item before the first item to be searched. Set to -1 to search from the beginning of the control. |

**Returns:** [Int32](https://docs.microsoft.com/dotnet/api/system.int32). The zero-based index of the first item found; returns -1 if no match is found, or 0 if the *text* parameter specifies [Empty](https://docs.microsoft.com/dotnet/api/system.string.empty).

### ![](/files/hsR4ok3152WyAf8J2C1u) GetSelected(index)

Returns a value indicating whether the specified item is selected.

| Parameter | Type                                                        | Description                                                              |
| --------- | ----------------------------------------------------------- | ------------------------------------------------------------------------ |
| **index** | [Int32](https://docs.microsoft.com/dotnet/api/system.int32) | The zero-based index of the item that determines whether it is selected. |

**Returns:** [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean). true if the specified item is currently selected in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md); otherwise, false.

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The specified index was outside the range of valid values.

### ![](/files/lzopMboA31bVq8UIcbT3) OnDataSourceChanged(e)

Fires the [DataSourceChanged](/api/wisej.web/lists-and-grids/listcontrol.md#datasourcechanged) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnDisplayMemberChanged(e)

Fires the [DisplayMemberChanged](/api/wisej.web/lists-and-grids/listcontrol.md#displaymemberchanged) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnLoad(e)

Fires the [Load](#load) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnReadOnlyChanged(e)

Fires the [ReadOnlyChanged](#readonlychanged) event.

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

### ![](/files/lzopMboA31bVq8UIcbT3) OnSelectedIndexChanged(e)

Fires the [SelectedIndexChanged](#selectedindexchanged) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnSortedChanged(e)

Fires the [SortedChanged](#sortedchanged) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnToolClick(e)

Fires the ToolClick event.

| Parameter | Type                                                                         | Description                                                                                                  |
| --------- | ---------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| **e**     | [ToolClickEventArgs](/api/wisej.web/editors/wisej.web.toolclickeventargs.md) | A [ToolClickEventArgs](/api/wisej.web/editors/wisej.web.toolclickeventargs.md) that contains the event data. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnValueMemberChanged(e)

Fires the [ValueMemberChanged](/api/wisej.web/lists-and-grids/listcontrol.md#valuememberchanged) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) OnWebEvent(e)

Processes the event from the client.

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

### ![](/files/lzopMboA31bVq8UIcbT3) OnWebRender(config)

Renders the client component.

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

### ![](/files/lzopMboA31bVq8UIcbT3) OnWebUpdate(state)

Updates the client component using the state information.

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

### ![](/files/lzopMboA31bVq8UIcbT3) 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. |

### ![](/files/lzopMboA31bVq8UIcbT3) RefreshItems()

Reloads all the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) items from the data source.

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectAll()

Selects all the items in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

### ![](/files/lzopMboA31bVq8UIcbT3) 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.                    |

### ![](/files/lzopMboA31bVq8UIcbT3) 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. |

### ![](/files/hsR4ok3152WyAf8J2C1u) SetSelected(index, selected)

Selects or clears the selection for the specified item in a [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

| Parameter    | Type                                                            | Description                                                                                                                      |
| ------------ | --------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------- |
| **index**    | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)     | The zero-based index of the item in a [ListBox](/api/wisej.web/lists-and-grids/listbox.md) to select or clear the selection for. |
| **selected** | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean) | true to select the specified item; otherwise, false.                                                                             |

**Throws:**

* [ArgumentOutOfRangeException](https://docs.microsoft.com/dotnet/api/system.argumentoutofrangeexception) The specified index was outside the range of valid values.
* [InvalidOperationException](https://docs.microsoft.com/dotnet/api/system.invalidoperationexception) The [SelectionMode](#selectionmode) property is set to None.

### ![](/files/lzopMboA31bVq8UIcbT3) Sort()

Sorts the items in the [ListBox](/api/wisej.web/lists-and-grids/listbox.md).

## Events

### ![](/files/hsR4ok3152WyAf8J2C1u) Load

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the [LazyLoading](#lazyloading) property is true and the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) is first shown.

When [LazyLoading](#lazyloading) is true An application may fill the items at any time prior to the [ListBox](/api/wisej.web/lists-and-grids/listbox.md) being shown, or while processing the [Load](#load) event.

### ![](/files/hsR4ok3152WyAf8J2C1u) ReadOnlyChanged

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the value of the [ReadOnly](#readonly) property has changed.

### ![](/files/hsR4ok3152WyAf8J2C1u) SelectedIndexChanged

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the [SelectedIndex](#selectedindex) property or the [SelectedIndices](#selectedindices) collection has changed.

### ![](/files/hsR4ok3152WyAf8J2C1u) SortedChanged

[EventHandler](https://docs.microsoft.com/dotnet/api/system.eventhandler) Fired when the [Sorted](#sorted) property has changed.

### ![](/files/hsR4ok3152WyAf8J2C1u) ToolClick

[ToolClickEventHandler](/api/wisej.web/editors/wisej.web.toolclickeventhandler.md) Fired when a [ComponentTool](/api/wisej.web/editors/wisej.web.componenttool.md) is clicked.

## Inherited By

| Name                                                               | Description                                                                                                                 |
| ------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------- |
| [CheckedListBox](/api/wisej.web/lists-and-grids/checkedlistbox.md) | Displays a [ListBox](/api/wisej.web/lists-and-grids/listbox.md) in which a check box is displayed to the left of each item. |

## Implements

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


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