Bind ItemsControl with ItemsSource to the array index - wpf

Question

I want to bind an ItemsControl to an array of object, using ItemsSource and DataTemplate.
And I want to show the index of each item.
Like
Customer 1:
Name: xxxx
Age:888
Customer 2:
Name: yyy
Age: 7777

Answer 1

The simplest way to do this is to add an Index property to you class ;-) Otherwise it can be done using a MultiValueConverter:
<Window x:Class="IndexSpike.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300"
xmlns:Converters="clr-namespace:IndexSpike"
xmlns:diag="clr-namespace:System.Diagnostics;assembly=WindowsBase"
Name="Root"
>
<Window.Resources>
<Converters:GetIndex x:Key="GetIndexConverter"/>
</Window.Resources>
<StackPanel>
<ItemsControl ItemsSource="{Binding Persons}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Margin="0,5,0,0">
<TextBlock.Text>
<MultiBinding Converter="{StaticResource
GetIndexConverter}"
StringFormat="Index: {0}">
<Binding Path="."/>
<Binding ElementName="Root" Path="Persons"/>
</MultiBinding>
</TextBlock.Text>
</TextBlock>
<TextBlock Text="{Binding Name, StringFormat='Name: {0}'}"/>
<TextBlock Text="{Binding Age, StringFormat='Age {0}'}"/>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</Window>
using System;
using System.Collections.ObjectModel;
using System.Globalization;
using System.Windows;
using System.Windows.Data;
namespace IndexSpike
{
public partial class Window1 : Window
{
public ObservableCollection<Person> Persons { get; set; }
public Window1()
{
Persons=new ObservableCollection<Person>
{
new Person("Me",20),
new Person("You",30)
};
InitializeComponent();
DataContext = this;
}
}
public class Person
{
public Person(string name,int age)
{
Name = name;
Age=age;
}
public string Name { get; set; }
public int Age { get; set; }
}
public class GetIndex:IMultiValueConverter
{
#region Implementation of IMultiValueConverter
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
var persons = (ObservableCollection<Person>) values[1];
var person = (Person) values[0];
return persons.IndexOf(person);
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
#endregion
}
}
Thanks to this question I found an other way to declare the MultiBinding:
<MultiBinding Converter="{StaticResource GetIndexConverter}"
StringFormat="Index: {0}">
<Binding Path="."/>
<Binding RelativeSource="{RelativeSource FindAncestor,
AncestorType={x:Type ItemsControl}}"
Path="DataContext.Persons"/>
</MultiBinding>