title: Any() does not compile in Portable Class Libraries; are there alternatives?
body: <p>How do I port the following statements to PCL?</p>
  
  <pre><code>using System.Linq;
  
  string value = ...;
  
  if (value.Any(ch =&gt; ch &gt; Byte.MaxValue)) {
      throw new ArgumentException("String contains non-ASCII characters.", "value");
  }
  </code></pre>
  
  <p>The code above does not compile and I always get the following error message:</p>
  
  <pre><code>Error   CS1061  'string' does not contain a definition for 'Any' and no
  extension method 'Any' accepting a first argument of type 'string' could be
  found (are you missing a using directive or an assembly reference?)
  </code></pre>