title: Using a BizTalk map to unescape XML in a particular node
body: <p>I have the following schema:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-16"?&gt;
  &lt;xs:schema xmlns="http://www.RedEyedMonster.co.uk/Integration/ESB" xmlns:b="http://schemas.microsoft.com/BizTalk/2003" elementFormDefault="qualified" targetNamespace="http://www.RedEyedMonster.co.uk/Integration/ESB" xmlns:xs="http://www.w3.org/2001/XMLSchema"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:appinfo&gt;
        &lt;b:schemaInfo is_envelope="no" xmlns:b="http://schemas.microsoft.com/BizTalk/2003" /&gt;
      &lt;/xs:appinfo&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:element name="ExternalEvent"&gt;
      &lt;xs:complexType&gt;
        &lt;xs:sequence&gt;
          &lt;xs:element minOccurs="1" maxOccurs="1" name="XmlType" type="xs:string" /&gt;
          &lt;xs:element minOccurs="1" maxOccurs="1" name="EscXml" type="xs:string" /&gt;
         &lt;/xs:sequence&gt;
      &lt;/xs:complexType&gt;
    &lt;/xs:element&gt;
  &lt;/xs:schema&gt;
  </code></pre>
  
  <p>Where EscXml contains escaped XML which can be quite complex. Is it possible to convert this in a map (i.e. unescape) to an  node or to the schema that will be derived from XmlType? </p>