title: XPath Expression to Return Nodes with Attributes of a Certain Length
body: <p>I need to grab all nodes of particular type within an XML document but only if their <em>value</em> attribute is not empty. I've tried a few permutations on the below, but with no luck:</p>
  
  <pre><code>".//Foo[not([@Value =''])]"
  </code></pre>