Visual Studio is not loading my debugger visualizer - visual-studio

Question

I wrote my own Debugger Visualizer.
It, and the attributes, are in their own assembly. There is no references or attributes in the assembly containing the class to be debugged - I want to make a drop-in dll that is optional for people to use.
The class I am trying to debug is a generic.
[Serializable]
public class FinCellTable<S> : IFinCellTable, IEnumerable<List<FinCell.IFinCell>>
where S : class, FinCell.IFinHeaderCell, FinCell.IFinCell, new()
Here is the visualizer:
[assembly: System.Diagnostics.DebuggerVisualizer(
typeof(Financials.Debugging.CellTableVisualizer),
typeof(VisualizerObjectSource),
Target = typeof(Financials.Transformation.IFinCellTable),
Description = "FinCell Table Visualizer")]
[assembly: System.Diagnostics.DebuggerVisualizer(
typeof(Financials.Debugging.CellTableVisualizer),
typeof(VisualizerObjectSource),
Target = typeof(Financials.Transformation.FinCellTable<Financials.FinCell.FinHeaderCell>),
Description = "FinCell Table Visualizer")]
namespace Financials.Debugging
{
public class CellTableVisualizer : DialogDebuggerVisualizer
{
protected override void Show(IDialogVisualizerService windowService, IVisualizerObjectProvider objectProvider)
{
if (windowService == null) throw new ArgumentNullException("windowService");
if (objectProvider == null) throw new ArgumentNullException("objectProvider");
var data = (IFinCellTable)objectProvider.GetObject();
using (var displayForm = new CellTableVizForm())
{
displayForm.PopulateForm(data);
windowService.ShowDialog(displayForm);
}
}
}
}
I am running Visual Studio 2010, and the following directory contains the .dll and .pdb of the Visualizer Assembly:
C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Packages\Debugger\Visualizers
I place a breakpoint on an instance of IFinCellTable that is specifically FinCellTable. It does not show the magnifying glass.
I debugged Visual Studio using another Visual Studio as the first VS was debugging. I watched the output window as the first VS loaded dll's. When I triggered a visualizer on a datatable, the second VS outputted that it loaded Microsoft.VisualStudio.DebuggerVisualizers.dll and Microsoft.VisualStudio.Debugger.DataSetVisualizer.dll (the latter from the correct directory I said above). (The Modules window behaves/shows the same.)
So obviously my Debugger Visualizer Drop-In assembly is not be loaded by VS, so it doesn't know to show the magnifying glass.
How do you get visual studio to load Visualizers up-front, so drop-in visualizers work and you don't need to edit your original code?

Answer 1

Wild guess: are you sure the correct files are in C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Packages\Debugger\Visualizers, not in C:\Users\<you>\AppData\Local\VirtualStore\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Packages\Debugger\Visualizers?
If yes, that's due to UAC Virtualization.

Answer 2

This question is over 5 years old, so I assume it's no longer relevant to the original poster, but for anyone else trying to do something similar:
System.Diagnostics.DebuggerVisualizer does not work when target is an interface. You have to specify a concrete type. You have to specify the attribute on every single concrete type you want to visualize:
[System.Diagnostics.DebuggerVisualizer("Financials.Debugging.CellTableVisualizer, Financials.Debugging, Version=1.0.0.0, Culture=neutral, PublicKeyToken=...")]
[Serializable]
public class FinCellTable<S> : IFinCellTable, IEnumerable<List<FinCell.IFinCell>>
where S : class, FinCell.IFinHeaderCell, FinCell.IFinCell, new()
{

Answer 3

I believe this can be disabled in Tools > Options:
If you do not see the effects of DebuggerDisplay or DebuggerTypeProxy ensure that Tools > Options > Debugging > General > Show raw structure of objects in variables windows is NOT checked.

Answer 4

The correct folder to place it is:
C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\Packages\Debugger\Visualizers. Once you place this DLL there and restart visual studio then you should get a "magnifying glass" over "Expression" type of variables (in debugging mode you will get it in watch window and also when you move your mouse cursor over the variable)