Use SOAP Toolkit 2.0 to provide existing code as a Web service

Use SOAP Toolkit 2.0 to provide existing code as a Web service
Use. NET to create distributed applications
Steve Kirk and Priya Dhawan
Microsoft Developer Network
Abstract: This article describes how to use Microsoft SOAP Toolkit Version 2.0 to convert existing Microsoft Visual Basic 6.0 code into data when it is provided as a Web service.
Directory
Introduction
Data types provided by existing code
ADO 2x Command object
ADO 2x Recordset object
Stream object
XMLDOM object
Summary
Introduction
Microsoft & reg; SOAP Toolkit Version 2.0 simplifies the provision and use of existing code as a Web service. The SOAP Toolkit 2.0 documentation (in English) in the SDK section of the MSDN Library describes this. Some of the main functions executed on the server side are to convert data and XML messages of different data types transmitted by the existing code (used between the Web service client and the server. The conversion of simple data types can be automatically processed. For more complex data types, developers must provide the conversion code.
When evaluating whether the existing code is suitable for providing Web services, the data conversion problem discussed in this article is not the only one that needs to be considered. Other factors to be considered include the object and state model, the returned data size, how to indicate success, how to return error information, and the security model (including access control, identity authentication and encryption) execution Model (synchronous or asynchronous), how to distribute code, and transaction Model (COM + transaction or declarative transaction. These issues will be discussed in the forthcoming architecture topic (English.
Data types provided by existing code
The conversion of all data types passed by existing code is a very large project. Therefore, this article describes some of the most common data types. An alternative solution for converting the SOAP Toolkit code is to use the XML interface to expand the existing code. This article discusses the following data type conversion methods:
ADO 2x Command object
ADO2x Recordset object
Stream object
XMLDOM object
ADO 2x Command object
The Command object of Microsoft ActiveX & reg; data object (ADO) is often provided for the existing code that directly accesses the database. Although the Command object cannot be passed between application layers running in different processes, it can be passed in the same process. For a single row of data entities, it is more efficient to return data through the output parameters of the Command object than to return data through the ADO record set. Therefore, the ADO Command object is very useful for returning a single row of entity data.