ListBox
Represents a control to display a list of items.
Last updated
Represents a control to display a list of items.
Last updated
The Wisej.Web.ListBox control displays a list of strings or data-bound values, allowing the user to select one or multiple options.
For a full list of properties, methods and events see the API documentation.
The ListBox control supports the inline Label property. This allows an application to set a label in relation to a ListBox control without having to create an additional Label control.
LabelsData binding is fully supported, including formatting and conversion of the value, through the default data binding infrastructure.
In addition to binding the value (Text, or SelectedItem or SelectedValue bindable properties), the ListBox control also supports data binding to populate the list using the DataSource property in conjunction with the DisplayMember, ValueMember, ToolTipMember and IconMember properties.
You can use DisplayMember, ValueMember, ToolTipMember and IconMember to name which properties to use from objects in the ListBox.Items list without binding to a DataSource.
When the ShowToolTips property is set to true, the ComboBox control uses the name specified in the ToolTipMember to read the tooltip text to display next to each item in the drop down list.
Data BindingThe ListBox control allows users to define one of several different selection modes for the control's configuration.
Selection Mode | Description |
---|---|
None | No items can be selected. |
One | Only one item can be selected. |
MultiSimple | Multiple items can be selected. |
MultiExtended | Multiple items can be selected, and the user can use the SHIFT, CTRL, and arrow keys to make selections. |
You can see the different configuration options shown below.
The ListBox control includes lazy loading support. Lazy loading works by sending the minimum number of records to the browser that is required for display within the control.
Lazy loading will significantly reduce waiting times related to rendering on the browser and network congestion caused by transferring large datasets from the server to the client (browser).
The ListBox control has the ability to use virtual scrolling, a feature that only renders the list items currently visible in the browser.
Using this option can drastically reduce the amount of time spent rendering in the browser for large datasets. For a List containing 25,000 strings, the effect will be a noticeable difference of several seconds.
Try the following sample code to test the loading times:
There are a few different ways to populate a ListBox control.
You can add a list of strings using the Items property of the ListBox control.
Alternatively, you can assign a list of items using the DataSource property of the control.
When assigning a list of complex objects to the DataSource or Items property, the objects will be converted into their string representations for display in the ListBox control unless the DisplayMember property is set.
Icon
Building off of the previous code snippet, it is easy to add an icon to the ListBox items.
IconMember, DisplayMember, ToolTipMember, and ValueMember retrieve and set the properties of the clicked data-bound item to use for the icon, text to display, tooltip text, and click value, respectively.
The icon paths specified in each object refer to the location of the image relative to the root of the project.
The above code will result in something similar to the following:
If you are working currencies, dates, or other forms of data, you might want to utilize the FormatString property of the ListBox control.
You only need to specify FormattingEnabled = true when using a DisplayMember.
The result will look something like this (dependent on system currency):
Item | Description |
---|---|
Class name | wisej.web.ListBox for the ListBox. wisej.web.listbox.ListItem for each list box item. |
Theme appearance | |
ListBox child components | |
List item child components | |
ToolContainer state | |
Source code |
"list", "listitem" for the items in the list box, see .
"scrollbar-x" is the horizontal scrollbar and "scrollbar-y" is the vertical scrollbar. See .
"checkbox" is the list item's checkbox. "icon" is the list item's icon. See .
"listbox", see .