Constructing Messages
You construct a message any time that you introduce a message into your orchestration, either by receiving it or by assigning values to a message variable. Any message that you construct must have a message type, so that the runtime engine has a complete description of the object that it is working with. The multi-part message type can be user-defined, it can be a .NET class, or it can be a schema. You can construct messages in various ways: you can invoke a .NET class to create a message, assign one message to another, or use a transform to map certain values within a message to values within another message. Messages are also constructed by a receive action or when your orchestration accepts a message as a parameter.
Note
A multi-part message type does not necessarily contain multiple parts; it might contain just one.
Important
Messages are immutable in BizTalk; that is, once you have constructed it, you cannot modify the original. If you need to make a change, you must construct a new copy of the message and assign values to it appropriately.
In This Section
How to Configure the Construct Message Shape
How to Configure the Message Assignment Shape
How to Configure the Transform Shape
Message References in Message Assignment Shape
Message References in User Code
Using XPaths in Message Assignments
Using Non-Canonical XPaths in Message Assignments
Constructing Messages in User Code
Appending Nodes to Messages in User Code