Calling .NET assembly or any out-of-box static methods in BizTalk Rule Engine (BRE)

Calling .NET assembly or any out-of-box static methods (like System.String.Concat etc) in BizTalk Rule Engine (BRE) is a simple stuff; there is not much documentation available for beginners.

For example, if the rule is

If CustomerType = ‘new’

THEN

WelcomeMessage = String.Concat(“Hello”, CustomerName)

In the above example, I need to use the “System.String.Concat” method from out-of-box mscrolib assembly (or any of your custom method from your helper class).

Executing from Orchestration:

Option 1:

By default, the rule engine requires you to assert all the facts, before they ca be executed. So to execute the rule which contains the .NET assembly or any out-of-box static methods, we must create an instance of the helper class and pass it as a parameter to the rules engine in the Call Rules shape.

So for the above rule, in the Orchestration

• Create an instance variable of type “String” - since we are calling the String.Concat() ( or the type of your helper class if you want to call a .NET assembly in your case)

• Passing the instance type as the parameter: In the “CallRules Policy Configuration” window, select the above created variable in the “Parameter Name” column.

Option2:

Modify the BRE’s behaviour of expecting us to assert the facts by changing the value of the StaticSupport registry key as specified in MSDN (http://msdn.microsoft.com/en-gb/library/aa950269%28BTS.20%29.aspx).

Registry key for 32-bit OS: [HKEY_LOCAL_MACHINE\Software\Microsoft\BusinessRules\3.0 ]

Registry key for 64-bit OS:[HKEY_LOCAL_MACHINE/SOFTWARE/Wow6432Node/Microsoft/BusinessRules/3.0]

For testing the rule in the BRE composer:

Follow: http://geekswithblogs.net/nsthompson/articles/ClassAndBusinessRulesEngineIntegration.aspx

I have not used the steps mentioned by Neil (in the referenced blog). I am not sure how we will use the fact retriever specific for “integrating the .NET” if you already using a fact retriever in your rule for some other purpose like caching the datatable/database connectionstring.

I have always used a test orchestration which invoked my rule. Yes, I have to deploy my rule before using the rule in the orchestration. That's the major downside of this method.