Having made the changes to your VMD file, you are in a position to test the new mappings with a larger sample of messages. As before, you will follow these steps:

• Regenerate the stubcode. This makes the new table definition available to the application.
• Recompile the application. This is necessary because you must incorporate the new table classes into the application.
• Use the HL7 Simulator to send test messages to the application.

To test your changes:

• Click the Stubcode icon in the toolbar. The Stubcode Generation Wizard appears.
• In the Prefix window, leave the default value, HL7, unchanged.
• From the Language list box, select C# - Visual Studio.NET 2005.
• From the Project Type list box, select Stubcode and Server Example.
• Click Generate to generate the classes for this application.
• Click Yes when asked whether you want to overwrite any existing stubcode.
• A dialog window opens, asking you if you would like to open the project. Click Yes to open the project.
• Compile the project.
• In the Stubcode Generation Window, click Close to close the window.

The following classes are generated for this application:

• One class for each defined message. In your case, you have two such classes: the 'PatientRegister' message class and the default message class.
• One pair of classes for each defined table: a table class and a table row class. In your case, you have two such pairs: the 'Patient' table pair and the 'NextOfKin' table pair.
• One Engine class. Recall that the engine contains a ParseMessage method that invokes the appropriate message-handling function. In your case, of course, there are two message-handling functions: OnPatientRegisterMessage and OnDefaultMessage.

	For more details on the classes generated for this application, see Using the Stubcode Generation Wizard.

Once you have compiled the project, you can test it by sending HL7 messages from the HL7 Simulator to the server. Use the same sample of test messages that you used before to send messages to the server.

For a message such as this:

MSH|^~\&|MESA_ADT|XYZ_ADMITTING|MESA_IS|XYZ_HOSPITAL|||ADT^A04|101160|P|2.5||||||||
EVN||200004230800||||200004230800
PID|||583220^^^ADT1||PANZA^SANCHO||16050601121520|M||AI||||||||20-98-3210|981276345|||||||||||
NK1|1|QUIXOTE^DON|MASTER|16 WINDMILL WAY^^LA MANCHA^SPAIN^12587|(157)383-6446
NK1|2|PANZA^TERESA|WIFE|1 ROSINANTE RD^^LA MANCHA^SPAIN^11212|(157)456-6390
NK1|2|CERVANTES^MIGUEL^DE|FATHER|65 ADIOS AVE^CELL 54^SEVILLE^SPAIN^11212|(157)259-6790
PV1||E||||||5101^NELL^FREDERICK^P^^DR|||||||||||V1102^^^ADT1|||||||||||||||||||||||||200004230800||||||||

the server should display output like this:

PatientRegister message parsed with data:
PatientId:583220
FirstName:Sancho
Surname:Panza
DateOfBirth:01/06/1605 12:15:20 PM
SocialSecurityNumber:981276345
Detail Table - NextOfKin
FirstName, Surname, RelationshipToPatient, PhoneNumber
Count of rows = 3
Row: 0
Don,Quixote,Master,(157)383-6446
Row: 1
Teresa,Panza,Wife,(157)456-6390
Row: 2
Miguel,Cervantes,Father,(157)259-6790

The message contains, in this case, three NK1 segments, and the information has been extracted from each segment.

This concludes the HL7 to Application tutorial. Now that you have finished it, you may wish to try the tutorial on generating HL7 messages called Application to HL7.