Question

When developing in C#, using functional-like methods such as Where, Select, Aggregate, etc. is really good for many reasons and I use them quite a lot. However, the Silverlight 4.0 Framework for Windows Phone 7.1 does not seem to include those. Is there any way to change that? I guess I can’t just change the mscorlib.dll to point to the one from the full .NET framework, or can I?

Answer 1

Caveat: I don’t do active WP7 development.

However! Spinning up a vanilla Windows Phone 7.1 project, and using the following, it works fine – both LINQ query-syntax and extension-method syntax work fine:

        var foo = from x in arr
                  where x%2 == 0
                  select x*2;
        var bar = foo.Average();

The only thing to note is that it is obtaining these methods from System.Core.dll, i.e. (if I browse it in the IDE):

// Type: System.Linq.Enumerable
// Assembly: System.Core, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e
// Assembly location: C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\Silverlight\v4.0\Profile\WindowsPhone71\System.Core.dll

So: just make sure you are referencing the System.Core.dll for Windows Phone 7.1

edit (see comments) : also check you have:

using System.Linq;

At the top of the file.