Making a webservice for an existing application

Question

There is an exisiting application made in vb6 , its an exe and now I want to make a webservice for this application, can anyone give me the insight to it, any sample code, books, examples? Please help! Thanks Nitin

nitin 0 · Answer

Thanks again for replying, actually I do not know myself why it was showing unreachable problem, but then I actually took out the statement from an existing method and wrote a fresh mehtod and it worked so I could compile it easily. Don#t ask me why it was not working before ;-) Moreover not all the classes are public in existing application so I cannot use most of the objects in my webservice, but finally it has been decided with my boss that I will write fresh code in c# step by step and I think that would be easier rather than debugging into legacy application code. Lets see , if I have doubts I will surely post the message, thanks again buddy for all your important responses. Take care, nitin

spgilmore · Answer

If this error is occurring in your C# code then... You can double-click on that line that says "Unreachable code detected" and it will take you to the line that it's referring to. You'll likely find that the code is in a method that is never called, or it occurs after an unconditional RETURN statement, etc. However, if I understand you correctly, it's telling you that there is unreachable code inside the automation server? I don't understand how that can happen. You're not compiling that code, so the compiler shouldn't check it. You also may have the source code, but the code is not actually in the reference. The referencd only contains the compiled code. How could the compiler tell if there was unreachable code? Lesser compilers have been known to introduce unreachable code, and the program still works, it's just larger than necessary, and the check is usually just put into place because unreachable code is often the result of an undetectable programming mistake. Hence, it is usually just a warning.

nitin 0 · Answer

Its an Activex exe and I have the source code also, I Added this exe as a reference in my webservice and now I can see in the object browser all the objects but when I try to instantiate the object I get on compilation "Unreachable code detected". The name of exe ActualProject.exe with namespace as ActualProject so when I write ActualProject.ApplicationClass TA = new ActualProject.ApplicationClass(); On compilation I get an error under ActualProject in the above line saying "Unreachable code detected". Can I use the code as I have access to all the objects? where is the mistake? Any ideas?

spgilmore · Answer

Though I doubt it, is the program an activex EXE (automation server)? If so, you can probably access the objects inside the .EXE just as if it was a DLL. While this is possible, I don't have a lot of faith in the .NET / COM interoperability, especially for a web service which needs to be stable. If you have the source code, you could probably rewrite the thing in C# if it's small.

james · Answer

This cannot be done throough a Web Service, you'd probably be best off just compiling it to an .exe file and allowing people to run it off the web server.

nitin 0 · Answer

The exe has a UI Tree View, and the vb project has lots of classes and forms. It connects to oracle database and returns the data from it. Normally if its a dll or control I can import them in .NET , making a reference in web service and then access all its objects but with exe do I have to individually reference the classes in webservice to access its objects or is there a way like dll and active x controls? Please reply!

james · Answer

What does the exe do? Does it return a value? Does it have a UI?

Making a webservice for an existing application

Answers (7)