MethodCall (BizTalk Server Sample)

The MethodCall sample demonstrates how to call a .NET-based method from a BizTalk Server orchestration.

What This Sample Does

This sample interacts with a .NET-based method using the following sequence of steps:

The BizTalk Server orchestration retrieves an XML input file from the In folder. This file contains information about an addition or subtraction you want the math library to perform.
The orchestration calls the included math library to perform the addition or subtraction specified in the XML input file.
The appropriate math library method, either Add or Subtract, performs the requested calculation and packages the result as an XML document.
The orchestration places the resulting .xml file in the Out folder.

This sample demonstrates the following functionalities:

Leveraging the promoted properties in an orchestration. The three elements in InputSchema.xsd are promoted as distinguished fields. When the orchestration receives the input message, it gets the values of these three fields and assigns them to the corresponding variables declared in the orchestration.
Using the Decide shape to express "if-then-else" logic in an orchestration. After the orchestration assigns the values of distinguished fields to internal variables, it enters the Decide shape to check whether an addition or subtraction should be performed. If no operation needs to be performed, the orchestration terminates.
Calling an external assembly from an orchestration. If an addition is to be performed, the orchestration calls an external C# assembly and passes in two parameters to perform the addition. The same procedures apply to a subtraction.

Note

You need to install the assembly to the global assembly cache before you can call it from the orchestration; otherwise you will receive an XLANG error during run time.
Using the Message Assignment shape to construct the output message.

Debugging the orchestration by putting the following code in the Expression shape:

System.Diagnostics.Debug.WriteLine(iResult);

You can also write the result to the event log by using:

System.Diagnostics.EventLog.WriteEntry("MethodCall SDK Sample Debug", System.String.Format("Result = {0}", iResult);

<Samples Path>\Orchestrations\MethodCall\

The following table shows the files in this sample and describes their purpose.

File(s)	Description
Cleanup.bat	Used to undeploy assemblies and remove them from the global assembly cache. Removes send and receive ports. Removes Microsoft Internet Information Services (IIS) virtual directories as needed.
Input.xml	Sample input file.
Setup.bat	Used to build and initialize this sample.
In the \MathLibrary folder: AssemblyInfo.cs, MathHelper.cs, MathLibrary.csproj	Project and source files for the math library used by this sample.
In the \MethodCallSample folder: InputSchema.xsd, OutputSchema.xsd	Schemas for the input and output .xml files, respectively.
In the \MethodCallSample folder: MethodCallSample.btproj, MethodCallSample.sln	Project and solution files for this sample.
In the \MethodCallSample folder: MethodCallSampleBinding.xml	Used for automated setup such as port binding.
In the \MethodCallSample folder: MethodCallService.odx	BizTalk Server orchestration that calls the math library to perform the requested calculation.

In a command window, navigate to the following folder:

<Samples Path>\Orchestrations\MethodCall
Run the file Setup.bat, which performs the following actions:
- Creates the input (In) and output (Out) folders for this sample in the MethodCall folder.
- Compiles the Visual Studio projects for this sample, and deploys the resulting assemblies.
- Creates and binds the BizTalk Server receive location, and the send and receive ports to the orchestration.
- Enables the receive location, and starts the send port. Enlists and starts orchestration.

Note

You should confirm that BizTalk Server did not report any errors during the build and initialization process before attempting to run this sample.

Paste a copy of the file Input.xml into the In folder.
Observe the .xml file created in the Out folder. This file contains the result of the requested addition or subtraction calculation. The format of the name of this file is <MessageID>.xml, where <MessageID> is the GUID generated to uniquely identify the message.
You can modify the input file to request different addition or subtraction calculations.

At a Visual Studio command prompt, change directory (cd) to <Samples Path>\Orchestrations\MethodCall\.
Run Cleanup.bat.