Question

I have a sorted listbox and need to display each item’s row number. In this demo I have a Person class with a Name string property. The listbox displays a a list of Persons sorted by Name. How can I add to the datatemplate of the listbox the row number???

XAML:

<Window x:Class='NumberedListBox.Window1'     xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'     xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'     Height='300' Width='300'>     <ListBox          ItemsSource='{Binding Path=PersonsListCollectionView}'          HorizontalContentAlignment='Stretch'>         <ListBox.ItemTemplate>             <DataTemplate>                 <TextBlock Text='{Binding Path=Name}' />             </DataTemplate>         </ListBox.ItemTemplate>     </ListBox> </Window> 

Code behind:

using System; using System.Collections.ObjectModel; using System.Windows.Data; using System.Windows; using System.ComponentModel;  namespace NumberedListBox {     public partial class Window1 : Window     {         public Window1()         {             InitializeComponent();              Persons = new ObservableCollection<Person>();             Persons.Add(new Person() { Name = 'Sally'});             Persons.Add(new Person() { Name = 'Bob' });             Persons.Add(new Person() { Name = 'Joe' });             Persons.Add(new Person() { Name = 'Mary' });              PersonsListCollectionView = new ListCollectionView(Persons);             PersonsListCollectionView.SortDescriptions.Add(new SortDescription('Name', ListSortDirection.Ascending));              DataContext = this;         }          public ObservableCollection<Person> Persons { get; private set; }         public ListCollectionView PersonsListCollectionView { get; private set; }     }      public class Person     {         public string Name { get; set; }     } } 

Answer 1

This should get you started:

http://weblogs.asp.net/hpreishuber/archive/2008/11/18/rownumber-in-silverlight-datagrid-or-listbox.aspx

It says it’s for Silverlight, but I don’t see why it wouldn’t work for WPF. Basically, you bind a TextBlock to your data and use a custom value converter to output the current item’s number.