Windows Forms Toolbox System.TypeInitializationException with UserControls

Question

I am using VS2015 to work on a Project using UserControls for Windows Forms. The last time I used the Controls everything worked fine and it had no display errors at all. However after restarting VS the Toolbox was unable to display the Controls.

When I start to add the Controls to other Forms it displays the error:

Error while creating the component ctrlObjectEditor.

Error message: System.TypeInitializationException

The Typeinitializer for "project.Log.LoggerHost" threw an Exception.

... (only rough translation)

When I run the Programm it works fine but I can not edit this in the Toolbox.

The Controls are all in the same Assembly. I have found other Questions but they dont seem to work for me. (e.g. AnyCPU, x64, x86, removing Logger from Controls)

Does anyone have an idea what could be wrong?

Answer 1

It seems I found the answer myself.

The Class FileLogger had a static Parameter filled with the value:

Path.GetDirectoryName(Assembly.GetEntryAssembly().Location)

It seems this Method causes an Exception when run by the designer so I replaced it with:

try
{
    var dir = Path.GetDirectoryName(Assembly.GetEntryAssembly()?.Location);
    return Path.Combine(dir, "Logs");
}
catch (ArgumentException)
{
    return "C:\\Logs";
}

And this seems to work.