Several days ago, we showed how XML documentation comments from source files were making their way into the quick info tips when editing C#/VB (via our SyntaxEditor .NET Languages Add-on for WPF/Silverlight).
Today I’d like to show the other half of that, namely how XML documentation comment files for .dlls can also be pulled in and have their contents displayed in quick info.
In the WPF add-on, any time a binary assembly (from a .dll) file is referenced, probing will take place to try and locate a related .xml documentation comment file. If found, it will be made available for use. We have an optimized design that streams its so that it’s never fully loaded in memory.
In the Silverlight add-on, we can’t access the normal folders where assemblies live due to security restrictions. However if the Silverlight application is full trust, or if it embeds the .xml documentation files via other mechanisms like manifest resources, it can manually wire up the documentation comment files for use.
Once documentation comment files are available to a binary assembly, the documentation for types/members can be displayed in quick info.
In the screenshot above, we hover over the List<T>.Add method call. Note how the summary documentation comments show.
In the next screenshot, we see a completion item description tip for the Enumerable.Count() extension method. Again the proper summary documentation comments show.
These features make it much easier for end users to know what each type/member does and bring the add-on one big step closer to VS-like editing capabilities. They will be in the next maintenance release.