title: XSD validate key value elements
body: <p>I have the following xml with subtype that has properties "name" and "type" and also a key valued properties.My question is how should I validate the properties element with XSD that it has the correct name of the keys (mask,interval,stream,useNetworkShare) and correct type of values - string in this case.</p>
  
  <pre><code> &lt;subtype name="testType" type="test"&gt;
          &lt;properties&gt;
            &lt;property key="mask" value="*" /&gt;
             &lt;property key="interval" value="10" /&gt;
             &lt;property key="stream" value="UnsortedSequential" /&gt;
             &lt;property key="useNetworkShare" value="false" /&gt;
          &lt;/properties&gt;
       &lt;/subtype&gt;
  </code></pre>