These last few days I’ve been working with the SQL Adapter for receiving messages in my orchestration and I’ve got stuck in a peculiar situation: one of the columns I was retrieving has an XML string as its value. The situation was that I wanted to create another message from that XML string after the reception of the SQL message.

In this post I’ll show how to create a message in an orchestration from an already created XML string.

In order to understand better the situation, let’s describe the scenario: 

• Suppose we have a SQL Table with three columns, for example: Id (uniqueIdentifier), occursOn(DateTime), configXML (varchar).
• Using the Wizard, I created the schema for retrieving the rows from the SQL table.
• Once received the message, which involves the three columns mentioned above, I wanted to create a new message from within the orchestration using the configXML value received in the SQL message. 

This can be achieved with the help of System.Xml.XmlDocument class. This class has a method called LoadXml( string xml ) which allows us to create an XmlDocument from an already created XML string. After loading the XML from the string, we can set this document to our message in Biztalk; this is possible because every message in Biztalk derives from XmlDocument. 

Here are the steps to follow to construct a message from an already existing XML string:

1.       Create the schema file for your already existing xml string

2.       Add a message of the type created in step 1 to your orchestration

3.       Add a variable of type System.Xml.XmlDocument to your orchestration

4.       Add a construct shape in order to construct your message of step 2

5.       Add an expression shape inside the construct shape with the following expression:  

In this example, varXMLDoc is the variable created in step 3; MySQLMessage.configXML is the XML string previously received in another message; and MySecondMessage is the message created in step 2.

That’s it, hope this to be useful!