It is possible to call web service from VB6 using Soap Toolkit 3.0. Soap Toolkit works the best when calling Web services created using Soap Toolkit 3.0 and COM objects. This is because Soap Tookit 3.0 comes with the WSDL tool that can generate both the WSDL and WSML files. The later is important in deserialze the soap message and map it to the COM objects on the client-side.

What happens to Web Services not created with Soap Toolkit 3.0? Those web services do not have WSML files. So we can either create WSML manually or create the customer mapper. The later essentially requires to walk through the IXMLDOMNodeList returned by soap call and create and set the properties of COM objects. 

I need a VB parser to analyze some VB programs. Searching on Google, I found two VB parsers. The first one was writen by Paul Vick who I believe is a Microsoft employee. It was written in VB.Net and will parser VB.Net 2005 and VB.Net 2003 files. The second one was written by Paul Cager. It was created using JavaCC (Java compiler compiler) and the parser is natually in Java. The parser will parse VB6. However, since the parser is generated from syntax defined in JJT file, it is possible to update the file to generate the parser for VB.NET.

Both parsers would generate abstract syntax tree. From there, we can walk the three to analyze the program.