A ListBox contains a collection of ListBoxItem objects. To select a ListBoxItem in a ListBox, set the IsSelected property to true.
Bind a ListBoxItem to data by binding the ItemsSource property of a ListBox to a data source. For more information, see How to: Bind a ListBox to Data. You can customize the appearance of a ListBoxItem by setting the ItemTemplate property of a ListBox to a DataTemplate. For more information, see Data Templating Overview.
By default, the HorizontalAlignment of a ListBoxItem is set to Stretch. The default horizontal position of a StackPanel is Center. If you set the Width property of a ListBoxItem through a StackPanel, the panel's default is applied and the item is centered.
Content Model: ListBoxItem is a ContentControl. Its content property is Content. For more information on the content model for ListBoxItem, see Controls Content Model Overview.
Dependency properties for this control might be set by the control’s default style. If a property is set by a default style, the property might change from its default value when the control appears in the application. The default style is determined by which desktop theme is used when the application is running. For more information, see Themes.