Tutorial: WCF COBOL Service using SQL

Walks you through the creation of a Windows Communication Foundation (WCF) service that interacts with the BookDemo base application.

In this tutorial you expose the functionality of the SqlBookWrapper program as a WCF service and use a console application as a client to communicate with it.


  • Review the Assumptions and Before you begin sections in the Tutorials: OpenESQL .NET Code topic to ensure that your environment is set up properly.
  • Before attempting this tutorial, you must first work through Tutorial: Prepare the SQL Server Environment.
  • The features demonstrated in this tutorial require that you have installed the Visual COBOL WCF Tools feature. If this feature is missing, see To install missing features from the IDE for installation instructions.

Demonstration solution - SqlBookWCF

The SqlBookWCF solution and project you create for this tutorial uses the following provided demonstration files in addition to the BookDemo base application:

In this tutorial, the sqlbook.cbl program is recompiled to .NET code without any changes. Recompiling the program exposes it as a class and exposes its main entry point as a static method. Its linkage section defines data as standard COBOL types, such as PIC X. Non-COBOL client programs do not understand these standard COBOL types. Therefore, you must map the standard COBOL types to .NET compatible types before communicating with the client program. This mapping is done by the SqlBookWrapper.cbl program.
Defines the WCF service and data contracts. Methods that define the operations in the SQLBookWrapper program are marked with the System.ServiceModel.OperationContract() attribute. These are exposed via service endpoints. The SqlBookWrapperWCF.SqlBook class marked with the DataContract attribute exposes the data from the SqlBookWrapper program.
The WCF service.
Defines service endpoints that enable the WCF service to call SqlBookWrapper code.
Note: The solution used in this tutorial is also provided with the Visual COBOL Samples Browser in completed form. To review the completed solution:
  1. Start the Visual COBOL Samples Browser. If you need instructions, see To start the Samples Browser.
  2. From the drop-down menu at the top of the Visual COBOL Samples Browser, select Show .NET only.
  3. In the left pane, click SQL.
  4. In the right pane, click OESQL - WPF Book (.NET, VS).


To complete this tutorial, progress through these topics in the order presented here. The bottom of each topic provides Next topic and Previous topic navigational links to help you proceed in the proper sequence: