WP7 System.Windows.Data unavailable to add as a reference

I need to use the IConverter class and understand its in the System.Windows.Data namespace. But this is unavailable when I go to add this as a reference.

I understand from other posts that somehow it may be tied up wi开发者_StackOverflow中文版th PresentationFramework.dll = but really not sure how I use this?

And still not sure why it is not available as are all the other references that I can easily add.

• thanks

PresentationFramework.dll is an assembly that contains the WPF framework. From your question you indicate that you are using Windows Phone 7, therefore your project should reference assemblies that are specifically part of the Windows Phone 7 framework.

IValueConverter is in the System.Windows.Data namespace and is located within the System.Windows assembly. It is part of the .NET framework subset available to Windows Phone 7 developers, so you will have no issue using it.