This article is an opener for any of you VB.NET programmers out there who might be working on an SAP implementation and integration with non-SAP systems. It is not an advanced article in the sense that the code is challenging,but it will help you with SAP integration,which itself can be challenging.

Understanding the Working Scenario

Suppose,for argument sake,that you have mySAP ERP R/3 version 4.x. Suppose further that you are tasked with using SAP's data in a non-SAP environment,a .NET environment. You have VB.NET 2.0 and Visual Studio 2005,and you have SAP client tools on your workstation as will everyone using your integration application. If these things are true,you already have everything you need to get started. (If not,it's going to be hard to try the example. However,with Microsoft Excel,VBA,and SAP client tools almost identical code will work.)

SAP (which translated from German—I think they get angry if you pronounce it "sap" but the temptation is there) means Systems,Applications,and Products. The ERP product—also often called SAP—exposes its capabilities through a variety of means,one of which is BAPIs (Business Application Programming Interface) and RFCs (Remote Function Calls). It is these BAPIs through COM Interop and VB.NET that you can call. And,that is where I will limit the discussion for now.

Note: It is worth noting that there are other tools such as the ERP .NET Connector that uses a technique much like importing a Web Service. I'll talk about this component/tool another time.

Retrieving Data from an SAP Implementation

Assuming all prior conditions mentioned are met,you can begin by creating a VB.NET project—I used a console application for the demo—and following these steps:

• In VS 2005,create a VB.NET console project
• Add a reference to SAPBAPIControlLib and SAPTableFactoryCtrl. This step will use tlbimp to generate COM Interop libraries,and your solution will actually link to Interop.SAPBAPIControlLib.dll and Interop.SAPTableFactoryCtrl.dll
• Add two Imports statements (see Listing 1) for each of these interop libraries
• And,write the rest of the code shown in Listing 1

Listing 1: Integrating VB.NET and mySAP ERP R/3 version 4.x using COM Interop.

Imports SAPBAPIControlLib
Imports SAPTableFactoryCtrl

Module Module1
   Sub Main()

      Dim bapi As Object
      Dim connection As Object

      bapi = CreateObject("SAP.Functions")
      connection = bapi.Connection

      If (connection.Logon(0,False)) Then

         Dim codes = bapi.Add("BAPI_COMPANYCODE_GETLIST")
         codes.call()
         Dim table As Table
         table = codes.Tables("COMPANYCODE_LIST")

         Dim I As Integer
         Dim j As Integer

         For I = 1 To table.RowCount
            For j = 1 To table.ColumnCount
               Console.Write(table.ColumnName(j) + ":")
               Console.WriteLine(table.Cell(I,j))
            Next
         Next

         Console.ReadLine()

      End If
   End Sub
End Module

The code in Listing 1 works because it uses late-bound,weakly typed objects. For example,bapi and connection are defined as an object,and I simply know that I can call connection.Logon to get SAP to show their login screen. The bapi.Add call indicates which BAPI function will be called and the table collection will hold the returned data table. The rest of the code just dumps the contents to the console.

There are variations you can add to this basic code. For example,you could copy the data from the table object to a DataSetor custom objects. You also could initialize the connection with pre-defined connection arguments entered literally or by a custom WindowsForm.

SAP's ERP implementation is a huge system. According to some literature and several consultants,there are upwards of 50,000 tables and probably that many BAPIs. As a result,there is ton of supporting infrastructure,but this code should get you started.

Summary

The mySAP ERP product is a generational system. If you are working on an SAP implementation,you have my sympathies. A lot of SAP's own code,comments,and tables are still in the original German. It is a mega-system in its own right,and if you have to master .NET and ABAP—one programming choice for SAP—and the SAP client tools,you have your work cut out for you.

Hopefully,this article demonstrated that integration with Windows is possible and basic operations aren't too difficult. Like everything else,though,challenges will be greater as your solution scales.

About the Author

Paul Kimmel is the VB Today columnist for