Question

Let’s say I have a class:

class Foo {   public string Bar   {     get { ... }   }    public string this[int index]   {     get { ... }   } } 

I can bind to these two properties using ‘{Binding Path=Bar}’ and ‘{Binding Path=[x]}’. Fine.

Now let’s say I want to implement INotifyPropertyChanged:

class Foo : INotifyPropertyChanged {   public string Bar   {     get { ... }     set     {       ...        if( PropertyChanged != null )       {         PropertyChanged( this, new PropertyChangedEventArgs( 'Bar' ) );       }     }   }    public string this[int index]   {     get { ... }     set     {       ...        if( PropertyChanged != null )       {         PropertyChanged( this, new PropertyChangedEventArgs( '????' ) );       }     }   }    public event PropertyChangedEventHandler PropertyChanged; } 

What goes in the part marked ????? (I’ve tried string.Format(‘[{0}]’, index) and it doesn’t work). Is this a bug in WPF, is there an alternative syntax, or is it simply that INotifyPropertyChanged isn’t as powerful as normal binding?

Answer 1

Thanks to Cameron’s suggestion, I’ve found the correct syntax, which is:

Item[] 

Which updates everything (all index values) bound to that indexed property.