You need to either use .NET Reflection to get a list of all the properties and methods, or write an XML parser tool to get the same list, and then generate the .JS source code.
I think both of them will require the same effort to write, but the Reflection approach can only be used with an ActiveX file — unless you have Visual Studio to create XML documentation.
If all you need is an "empty shell" .JS file for properties and methods, then the code in this article should provide a good foundation:
http://www.codeproject.com/KB/dotnet/Reflection.aspx
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