title: How to define xsi:type as an attribute in XML-schema?
body: <p>I have an XML for which I want to write a schema definition. The problem is that I don't know how to define xsi:type as an attribute. Here is the XML element:</p>
  
  <pre><code>&lt;SerializedData xsi:type="xs:double"&gt;300.0&lt;/SerializedData&gt;
  </code></pre>
  
  <p>My XML-schema definition so far looks like this:</p>
  
  <pre><code>&lt;complexType name="SerializedDataType"&gt;
      &lt;simpleContent&gt;
          &lt;extension base="double"&gt;
  
          &lt;/extension&gt;
      &lt;/simpleContent&gt;
  &lt;/complexType&gt;
  </code></pre>
  
  <p>I have also tried defining it like Ian Roberts suggested:</p>
  
  <pre><code>&lt;element name="SerializedData"/&gt;
  </code></pre>
  
  <p>However, when I use BPEL designer to initialize it like this:</p>
  
  <pre><code>&lt;SerializedData xsi:type="xs:double"&gt;300.0&lt;/SerializedData&gt;
  </code></pre>
  
  <p>I get the following warning:</p>
  
  <blockquote>
    <p>The fixed value you entered does not appear to be valid XML (which is required for some types of fixed values to work correctly). It will be saved in a text format.</p>
  </blockquote>
  
  <p>If I initialize it like this there is no warning:</p>
  
  <pre><code>&lt;SerializedData&gt;300.0&lt;/SerializedData&gt;
  </code></pre>
  
  <p>But the problem is that the Web Service I am trying to invoke expects the request SOAP message to include the attribute xsi:type="xs:double". How can I make my SOAP request message to include it?</p>
  
  <p>Any help would be greatly appreciated!</p>