using existing assemblies in a WS

Question

okay this is probably a dumb question bu I'm not so proud that I can't ask those now and then. I have a class in an assemble that already exists. My class calulates the distance between zip codes (quite handy). I want to expose this on my web service. In the original class the distance() method does not have a [WebMethod] attribute. So my question is what is the best procedure for exposing that class in my WS? Now granted I have the source code and I could cut/paste it into the WS project quite easily. But I'm 99% certain thats the wrong way to do it as it would defeat the purpose of creating seperate reusable assemblies. So can anyone point me in the right direction? Do I need do extend the class to a generic and override the method? That doesn't seem right either.. Is there an easier and more 'correct' way to do this? -James

james · Answer

Thanks for the response... very good answer

david 0 · Answer

Additionally you can create a class that automatically (dynamically) does the same thing by reflecting off your original assembly. This may pose some problems if you only want to expose certain methods or need to use different aregument types.

david 0 · Answer

void MyOriginalFunction(...) // In the original assembly In a new assembly that references the original... [WebMethod] void MyWebMethod(...) { MyClass MyObject = new MyClass(); MyObject.MyOriginalFunction(...) }

james · Answer

Right but for any method to be 'visible' on a WS it has to have the [WebMethod] attribute on it. i.e... [WebMethod] public double Distance(string ZipCode1 string ZipCode2) { // calculation logic here } However if when I originally created my assembly I did not have that attribue on it.. How could I then expose that method through my Web Service? What I'm trying to avoid is cutting/pasting the class into my WS project or recompiling my original assembly. Granted I CAN do it either of those ways but they are archaic ways of dealing with assemblies. I'm looking for the Best Practice for this type of thing. -James

katana · Answer

Ok I'm confused a little. I would have my WebService only reference the other assembly. The other assembly wouldn't know whether it is being called via the WebService or from a Windows Form. Morgan

james · Answer

Morgan That would work except that I have to have the [WebMethod] attribue set for each Method I want exposed over the WS. If it isn't like that in the original assembly how could I add it after the fact? -James

katana · Answer

I would create a WS that would simply use the assembly. Instantiate an object that uses the current assembly. Think of the WebService as a wrapper around the Assembly. Morgan