# ListControlExtensions

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 [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md) class.

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

```csharp
public class ListControlExtensions
```

{% endtab %}

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

```visual-basic
Public Class ListControlExtensions
```

{% endtab %}
{% endtabs %}

## Methods

### ![](/files/lIX317sDtMTZJBi9oSIx) AllowHtml\<TListControl>(listControl, value)

Sets the AllowHtml property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the AllowHtml property.                                                     |
| **value**        | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                            | A boolean indicating whether HTML content is allowed in the list items.                                       |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated AllowHtml property.

This method allows you to enable or disable HTML content in the list items.

```csharp

myListControl.AllowHtml(true);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) BorderStyle\<TListControl>(listControl, borderStyle)

Sets the BorderStyle property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the BorderStyle property.                                                   |
| **borderStyle**  | [BorderStyle](/api/wisej.web/enumerations/wisej.web.borderstyle.md)                        | The [BorderStyle](#borderstyle``1) value to set for the list control.                                         |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated BorderStyle property.

This method allows you to set the border style for the list control.

```csharp

myListControl.BorderStyle(BorderStyle.FixedSingle);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) DataSource\<TListControl>(listControl, value)

Sets the DataSource property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the DataSource property.                                                    |
| **value**        | [Object](https://docs.microsoft.com/dotnet/api/system.object)                              | The data source to bind to the list control.                                                                  |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated DataSource property.

This method allows you to set the data source for the list control.

```csharp

myListControl.DataSource(myDataSource);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) DisplayMember\<TListControl>(listControl, value)

Sets the DisplayMember property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the DisplayMember property.                                                 |
| **value**        | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The property to display for the list items.                                                                   |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated DisplayMember property.

This method allows you to set the property to display for the list items.

```csharp

myListControl.DisplayMember("Name");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) FormatInfo\<TListControl>(listControl, provider)

Sets the FormatInfo property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                               |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).             |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the FormatInfo property.                                                                |
| **provider**     | [IFormatProvider](https://docs.microsoft.com/dotnet/api/system.iformatprovider)            | The [IFormatProvider](https://docs.microsoft.com/dotnet/api/system.iformatprovider) to use for formatting the list items. |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated FormatInfo property.

This method allows you to set the format provider for the list control.

```csharp

myListControl.FormatInfo(CultureInfo.CurrentCulture);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) FormatString\<TListControl>(listControl, format)

Sets the FormatString property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the FormatString property.                                                  |
| **format**       | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The format string to use for displaying the list items.                                                       |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated FormatString property.

This method allows you to set the format string for the list control.

```csharp

myListControl.FormatString("C2");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) FormattingEnabled\<TListControl>(listControl, value)

Sets the FormattingEnabled property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the FormattingEnabled property.                                             |
| **value**        | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                            | A boolean indicating whether formatting is enabled for the list items.                                        |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated FormattingEnabled property.

This method allows you to enable or disable formatting for the list control.

```csharp

myListControl.FormattingEnabled(true);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) IconMember\<TListControl>(listControl, value)

Sets the IconMember property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the IconMember property.                                                    |
| **value**        | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The property to use as the icon for the list items.                                                           |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated IconMember property.

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

```csharp

myListControl.IconMember("IconPath");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) Invalid\<TListControl>(listControl, value)

Sets the Invalid property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the Invalid property.                                                       |
| **value**        | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                            | A boolean indicating whether the list control is in an invalid state.                                         |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated Invalid property.

This method allows you to set the invalid state for the list control.

```csharp

myListControl.Invalid(true);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) InvalidMessage\<TListControl>(listControl, message)

Sets the InvalidMessage property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the InvalidMessage property.                                                |
| **message**      | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The message to display when an invalid operation occurs in the list control.                                  |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated InvalidMessage property.

This method allows you to set a custom invalid message for the list control.

```csharp

myListControl.InvalidMessage("Invalid selection.");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) OnSelectedValueChanged\<TListControl>(listControl, action)

Attaches an event handler for the SelectedValueChanged event of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control to attach the event handler to.                                                              |
| **action**       | [Action\<TListControl>](https://docs.microsoft.com/dotnet/api/system.action-1)             | An action to execute when the SelectedValue property changes.                                                 |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the attached SelectedValueChanged event handler.

This method allows you to execute a custom action whenever the SelectedValue property of the list control changes.

```csharp

myListControl.OnSelectedValueChanged(lc =>
{
AlertBox.Show("Selected value changed!");
});

```

### ![](/files/lIX317sDtMTZJBi9oSIx) PrefetchItems\<TListControl>(listControl, count)

Sets the PrefetchItems property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the PrefetchItems property.                                                 |
| **count**        | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)                                | The number of items to prefetch for the list control.                                                         |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated PrefetchItems property.

This method allows you to set the number of items to prefetch for the list control.

```csharp

myListControl.PrefetchItems(50);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) SelectedIndex\<TListControl>(listControl, value)

Sets the SelectedIndex property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the SelectedIndex property.                                                 |
| **value**        | [Int32](https://docs.microsoft.com/dotnet/api/system.int32)                                | The index to select in the list control.                                                                      |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated SelectedIndex property.

This method allows you to set the selected index for the list control.

```csharp

myListControl.SelectedIndex(0);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) SelectedValue\<TListControl>(listControl, value)

Sets the SelectedValue property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the SelectedValue property.                                                 |
| **value**        | [Object](https://docs.microsoft.com/dotnet/api/system.object)                              | The value to select in the list control.                                                                      |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated SelectedValue property.

This method allows you to set the selected value for the list control.

```csharp

myListControl.SelectedValue(someValue);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) ShowToolTips\<TListControl>(listControl, value)

Sets the ShowToolTips property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the ShowToolTips property.                                                  |
| **value**        | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                            | A boolean indicating whether tooltips should be shown for the list items.                                     |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated ShowToolTips property.

This method allows you to enable or disable tooltips for the list items.

```csharp

myListControl.ShowToolTips(true);

```

### ![](/files/lIX317sDtMTZJBi9oSIx) ToolTipMember\<TListControl>(listControl, value)

Sets the ToolTipMember property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the ToolTipMember property.                                                 |
| **value**        | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The property to use as the tooltip for the list items.                                                        |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated ToolTipMember property.

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

```csharp

myListControl.ToolTipMember("Description");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) ValueMember\<TListControl>(listControl, value)

Sets the ValueMember property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the ValueMember property.                                                   |
| **value**        | [String](https://docs.microsoft.com/dotnet/api/system.string)                              | The property to use as the value for the list items.                                                          |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated ValueMember property.

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

```csharp

myListControl.ValueMember("ID");

```

### ![](/files/lIX317sDtMTZJBi9oSIx) VirtualScroll\<TListControl>(listControl, value)

Sets the VirtualScroll property of the specified [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md).

| Parameter        | Type                                                                                       | Description                                                                                                   |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------- |
| **TListControl** |                                                                                            | The type of the list control, must inherit from [ListControl](/api/wisej.web/lists-and-grids/listcontrol.md). |
| **listControl**  | [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md) | The list control for which to set the VirtualScroll property.                                                 |
| **value**        | [Boolean](https://docs.microsoft.com/dotnet/api/system.boolean)                            | A boolean indicating whether virtual scrolling is enabled for the list control.                               |

**Returns:** [TListControl](/api/wisej.web.markup/extensions/wisej.web.markup.listcontrolextensions.md). The modified list control with the updated VirtualScroll property.

This method allows you to enable or disable virtual scrolling for the list control.

```csharp

myListControl.VirtualScroll(true);

```


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