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How to instantiate IModule-inheriting class from an AppDomain?

I'm a bit confused here and haven't gotten much help from google. Here's what I'm trying to do:
public Boolean LoadModule(String moduleHandle)//name of module MUST match its .dll name. Name of AppDomain is the same as the Handle.
{
try
{
AppDomain moduleDomain = AppDomain.CreateDomain(moduleHandle);
String pathToDll = #"C:\IModules.dll"; //Full path to dll you want to load
Type moduleType = typeof(IModule);
IModule loadedModule = (IModule)moduleDomain.CreateInstanceFromAndUnwrap(pathToDll, moduleType.FullName);
ModuleList.Add(loadedModule, moduleDomain);
Broadcast("Module loaded: " + moduleHandle, ModuleManagerHandle);
return true;
}
catch (Exception e)
{
//console writeline the error? probably cant
OutputBox.AppendText(e.ToString() + Environment.NewLine);
return false;
}
}
I thought I finally had this figured out but when I try to instantiate the IModule (ConsoleModule, in this case), I get the following error:
System.MissingMethodException: Constructor on type 'IModules.IModule' not found.
I take this to mean that I need to have a constructor, as if this were a class object instantiating itself on this function call, but I cannot make an interface have a constructor.
I have seen other threads suggesting ways to solve this problem, but they use assembly instead of appdomain, which will mess up the ability to unload modules. I'm concerned that without the ability to unload modules the application will suffer memory bloating over time.
The end goal is to be able to write a module, leave the program running and load/unload the modules during runtime without any changes to the core program, and add functionality on the go.
Anyone know of a workaround or maybe a better way to deal with dynamic module loading and unloading?

This is fixed with .NET 5.0 AssemblyLoadContext:
var basePath = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);
AssemblyLoadContext moduleAssemblyLoadContext = new AssemblyLoadContext(moduleHandle, true);
Assembly moduleAssembly = moduleAssemblyLoadContext.LoadFromAssemblyPath($"{basePath}\\{moduleHandle}.dll");
Type[] types = moduleAssembly.GetTypes();
foreach (Type type in types)
{
// Does this class support the transport interface?
Type typeModule = type.GetInterface("IModule");
if (typeModule == null)
{
// Not supported.
continue;
}
// This class supports the interface. Instantiate it.
IModule loadedModule = moduleAssembly.CreateInstance(type.FullName) as IModule;
if (loadedModule != null)
{
loadedModule.LoadedModule(this);
ModuleList.Add(loadedModule, moduleAssemblyLoadContext);
Broadcast("Module loaded: " + moduleHandle, ModuleManagerHandle);
OutputTextBox.AppendText(moduleHandle + " was loaded." + Environment.NewLine);
// Successfully created the interface. We are done.
return true;
}
}
return false;
Can't find the source anymore but found it looking for a related problem (you can find it on MSDN anyways). This successfully loads and unloads assemblies into their context. User must set the isCollectible value to TRUE to enable full unloading.
Only issue I had is that .NET 5.0 is not compatible -with itself- yet and libraries loaded as .NET 5.0 into .NET 5.0 programs will give a BadImageFormatException when trying to load the assembly. To fix, set the LIBRARY to the next most recent target framework (in my case, .NET Core 3.1) and move the newly compiled dll to wherever it goes and the application should run using the new dll.

The error tells you that there is no default (empty) constructor found for the type IModule. Since IModule is an interface, the message seems to make some sense.
Resulotion: Instantiate a class that implements IModule. An interface can never be intantiated on its own.
To instantiate the class, just one line neds to be changed:
Type moduleType = typeof(ClassThatImplementIModule);
You can still cast the instance to IModule

Getting the StartArguments from a VSIX plugin for .NET Core projects

EDIT - Looks like the initial problem only applies to .NET Core projects. So the question shifts to "What is the correct way to get the full range of project properties from .NET Core projects?"
I'm writing a Visual Studio 2019 plugin that uses some of the project configuration settings. It seems straight forward enough to get the Project object (C# here, but also C++ & others) and then spelunking the Configuration's for Property objects.
But it appears that accessing most of the properties will throw System.NotImplementedException.
Primary Question: Is there another way to access these settings - like startup arguments and other debugging configuration?
Secondary Question: Are there any good resources on this stuff? The online MS docs are a bit terse for my taste.
void ProcessCSharpProject(VSProject csProj)
{
foreach (var config in csProj.Project.ConfigurationManager.Cast<Configuration>())
{
Property debugInfoProp = config.Properties.Item("DebugInfo");
var debugInfo = debugInfoProp.Value as String; // works
Property startArgsProp = config.Properties.Item("StartArguments");
var startArgs = startArgsProp.Value as String; // NotImplemented
// Another way to access the same thing:
var configProps = config.Object as CSharpProjectConfigurationProperties6;
var startArgs2 = configProps.StartArguments; // Also NotImplemented
}
}
Thanks!

PortableDeviceManagerClass in C# not able to initialize

I have a c# library which provides some functionallity to upload data onto connected (android) devices. The dll itself gets exported via UnmangedExports to be used by an delphi application.
Here is the function which gets called by the delphi application:
[DllExport]
[return: MarshalAs(UnmanagedType.LPStr)]
public static string getDevices()
{
try
{
var devices = string.Empty;
var collection = new PortableDeviceCollection();
collection.Refresh();
foreach (var device in collection)
{
device.Connect();
if (devices != string.Empty)
{
devices += ";";
}
devices += device.FriendlyName;
device.Disconnect();
}
return devices;
}
catch (Exception e)
{
SomeClass.WriteErrorToLogFile(e);
return "ERROR";
}
}
Here is the class PortableDeviceCollection:
public class PortableDeviceCollection : Collection<PortableDevice>
{
private readonly PortableDeviceApiLib.PortableDeviceManagerClass _deviceManager;
public PortableDeviceCollection()
{
this._deviceManager = new PortableDeviceApiLib.PortableDeviceManagerClass();
}
public bool Refresh()
{
this._deviceManager.RefreshDeviceList();
// Determine how many WPD devices are connected
var deviceIds = new string[1];
uint count = 1;
this._deviceManager.GetDevices(null, ref count);
if (count > 0)
{
// Retrieve the device id for each connected device
deviceIds = new string[count];
this._deviceManager.GetDevices(deviceIds, ref count);
foreach (var deviceId in deviceIds)
{
Add(new PortableDevice(deviceId));
}
return true;
}
else
return false;
}
}
I can create the dll with visual studio and use this inside of the delphi application. When the delphi application calls the getDevices() function, i get an error on the instantiation of the PortableDeviceCollection class:
The file or assembly "Interop.PortableDeviceApiLib, Version = 1.0.0.0,
Culture = neutral, PublicKeyToken = null" or a dependency of it was
not found. The assembly is created by a runtime that is more recent
than the currently loaded runtime and can not be loaded.
ProductXY.PortableDeviceCollection..ctor()
ProductXY.ProductXYMain.getDevices()
The targetframework for the c# project is set to .Net Framework 4. Using any lower version i get an error when i try to compile the project:
The primary reference "Interop.PortableDeviceApiLib" could not be
resolved because it has an indirect dependency on the .NET Framework
assembly "mscorlib, version = 4.0.0.0, Culture = neutral,
PublicKeyToken = b77a5c561934e089", which is a higher version 4.0.0.0
than version 2.0.0.0 in the current target framework.
Please note. I have neither written the c# library nor the delphi application. Both have worked together for years. Now i have to add a functionallity to the c# library. I have not added any code to the project. I just tried to compile it again and use the dll. The only thing i did was updating the RGiesecke.DLLExport.Metadata via NuGet Packetmanager. Without updating i got an error
"Microsoft.Build.Utilities.ToolLocationHelper could not find
ildasm.exe"
I am aware of this Enumerating Windows Portable Devices in C# question. But my error is thrown before the code which is treaded by the question is reached. I still tried the solution to the question, but the action (deassamble, find and replace in the dll) which is described in the answere has already been done (otherwise my code would not have compiled).
The error message doesn't make sense to me. Interop.PortableDeviceApiLib is a COM-Lib which is not available for download in different framework-versions. I think I am missing something here.
Can anyone help me?

I was finally able to solve this problem. To be honest I don't know what finally solved this. For every one who stumbles up on this, here are the things i tried to fix this problem. They are in no specific order (since i tried everything multiple times):
Updating the RGiesecke.DLLExport packet
Changing the plattform in the Konfigurations-Manager to x86
Disassamble, edit and reassable the Interop.PortableDeviceApiLib like in this question (answeres of Christophe Geers and Bruno Klein)
Delete the reference to the Interop.PortableDeviceApiLib
Delete the reference to the Interop.PortableDeviceTypesLib
Readding the reference to the Interop.PortableDeviceApiLib
Readding the reference to the Interop.PortableDeviceTypesLib
Rebuild the project
Setting the Interoptyp embeddet on both to false (I found various statements to NOT do this, but the project was set up like this when i got it and it worked (be carefull)) on both Interop-Libs.
At least this helped me.

How can I know if this method is supported in Windows Mobile?

There are some classes (of the .NET framework 3.5) that contain some methods that are supported in .NET Compact Framework, and some methods that are not supported. There are also some classes that does not exists for the .NET Compact Framework.
For example for the System.IO.File class, the File.Create function is supported by .NET Compact Framework, but the File.Encrypt function is not.
Another example: the System.IO.File class is supported by .NET Compact Framework, but the System.Diagnostic.StackTrace is not.
I need to tell to the compiler something like this:
#ifdef COMPACT_FRAMEWORK // I'm compiling this from a smart device project
MyEncryptMethod("filename");
#else // I'm compiling this from a desktop project
File.Encrypt("filename");
#endif
How can I do?
(The specific version is Windows Mobile 6.1 Professional).

Just to add, since you are showing windows-mobile and windows-mobile-6, you should change your #define constraint to PocketPC instead of COMPACT_FRAMEWORK.
#ifdef PocketPC // PocketPC is what the WM SDK uses
MyEncryptMethod("filename");
#else // I'm compiling this from a desktop project
File.Encrypt("filename");
#endif
Update:
Nick: What yms said. :) When building a project using one of the Smart Device projects, Visual Studio automatically add the conditional compilation symbol PocketPC to the project.
From within VS2008's Main Menu, click Project and select your project's Properties at the bottom.
On your project's Properties page, go to the Build tab, and there you will see where PocketPC is already defined for you.

The code you provided is good, you just have to define the COMPACT_FRAMEWORK compilation symbol.
First, define a build configuration that you'll use when building your assembly for the compact framework. Then, in this build configuration, just define the COMPACT_FRAMEWORK conditional compilation symbol.
Conditional compilation symbols are defined in the Build tab of the project properties.

Here is some code the looks for a Method inside a class:
public static bool execCmd(string sFunc, string sArg, ref string sResponse)
{
bool bRet = true;
try
{
// Instantiate this class
myCommands cmbn = new myCommands(sFunc, sArg);
// Get the desired method by name: DisplayName
//MethodInfo methodInfo = typeof(CallMethodByName).GetMethod("DisplayName");
MethodInfo methodInfo = typeof(myCommands).GetMethod(sFunc);
// Use the instance to call the method without arguments
methodInfo.Invoke(cmbn, null);
sResponse = cmbn.response;
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("Exception in execCmd for '" + sFunc + "' and '" + sArg + "' " + ex.Message);
bRet = false;
}
return bRet;
}
You have to change myCommands to the class you are searching and sFunc has to be set to the Method you are looking for. With that code you can check if a method exists in a class.
~josef

Build-time code validation and generation based upon code files across projects

I'm looking for a method that let's me validate code and generator code as part of the build process, using Visual Studio 2010 (not express) and MSBuild.
Background Validation:
I'm writing a RESTful web service using the WCF Web Api. Inside the service class that represents the web service I have to define an endpoint, declaring additionally parameters as plain test. When the parameter name inside the endpoint declaration differs from the parameter of the C# method I get a error - unfortunately at run time when accessing the web service, not at compile time. So I thought it would be nice to analyze the web service class as part of the compile step for flaws like this, returning an error when something is not right.
Example:
[WebGet(UriTemplate = "Endpoint/{param1}/{param2}")]
public string MyMethod(string param1, string parameter2) {
// Accessing the web service now will result in an error,
// as there's no fitting method-parameter named "param2".
}
Also I'd like to enforce some naming rules, such as GET-Methods must start with the "Get" word. I believe this will help the service to remain much more maintainable when working with several colleagues.
Background Generation:
I will be using this REST web service in a few other projects, there for I need to write a client to access this service. But I don't want to write a client for each of these, always adjusting whenever the service changes. I'd like the clients to be generated automatically, based upon the web service code files.
Previous approach:
So far I tried to use a T4 template using the DTE interface to parse the code file and validate it, or generate the client. This worked fine in Visual Studio when saving manually, but integrating this in the build process turned out to be not so working well, as the Visual Studio host is not available using MSBuild.
Any suggestion is welcome. :)

Instead of using DTE or some other means to parse the C# code you could use reflection (with Reflection-Only context) to examine the assembly after it's compiled. Using reflection is a more robust solution and probably faster also (especially if you use Mono.Cecil to do the reflecting).
For the MSBuild integration I would recommend writing a custom MSBuild task - it's fairly easy and more robust/elegant than writing a command line utility that's executed by MSBuild.

This may be a long shot but still qualifies as "any suggestion" :)
You could compile the code, then run a post-build command which would be a tool that you'd have to write which uses reflection to compare the parsed UriTemplate text with the method parameter names, catching errors and outputting them in a manner that MSBuild will pickup. Look at This Link for information on how to output so MSBuild will put the errors in the visual studio error list. The post-build tool could then delete the compiled assemblies if errors were found, thus "simulating" a failed build.
Here's the SO Link that lead me to the MSBuild Blog too, just for reference.
HTH

For the enforcement side of things, custom FxCop rules would probably be a very good fit.
For the client code generation, there are quite a few possibilities. If you like the T4 approach, there is probably a way to get it working with MSBuild (but you would definitely need to provide a bit more detail regarding what isn't working now). If you're want an alternative anyway, a reflection-based post-build tool is yet another way to go...

Here is a short, extremely ugly program that you can run over an assembly or group of assemblies (just pass the dlls as arguments) to perform the WebGet UriTemplate check. If you don't pass anything, it runs on itself (and fails, appropriately, as it is its own unit test).
The program will print out to stdout the name of the methods that are missing the parameters and the names of the missing parameters, and if any are found, will return a non-zero return code (standard for a program failing), making it suitable as a post-build event. I am not responsible if your eyes bleed:
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using System.ServiceModel.Web;
namespace ConsoleApplication1
{
class Program
{
static int Main(string[] args)
{
var failList = new ConcurrentDictionary<MethodInfo, ISet<String>>();
var assembliesToRunOn = (args.Length == 0 ? new[] {Assembly.GetExecutingAssembly()} : args.Select(Assembly.LoadFrom)).ToList();
assembliesToRunOn.AsParallel().ForAll(
a => Array.ForEach(a.GetTypes(), t => Array.ForEach(t.GetMethods(BindingFlags.Public | BindingFlags.Instance),
mi =>
{
var miParams = mi.GetParameters();
var attribs = mi.GetCustomAttributes(typeof (WebGetAttribute), true);
if (attribs.Length <= 0) return;
var wga = (WebGetAttribute)attribs[0];
wga.UriTemplate
.Split('/')
.ToList()
.ForEach(tp =>
{
if (tp.StartsWith("{") && tp.EndsWith("}"))
{
var tpName = tp.Substring(1, tp.Length - 2);
if (!miParams.Any(pi => pi.Name == tpName))
{
failList.AddOrUpdate(mi, new HashSet<string> {tpName}, (miv, l) =>
{
l.Add(tpName);
return l;
});
}
}
});
})));
if (failList.Count == 0) return 0;
failList.ToList().ForEach(kvp => Console.Out.WriteLine("Method " + kvp.Key + " in type " + kvp.Key.DeclaringType + " is missing the following expected parameters: " + String.Join(", ", kvp.Value.ToArray())));
return failList.Count;
}
[WebGet(UriTemplate = "Endpoint/{param1}/{param2}")]
public void WillPass(String param1, String param2) { }
[WebGet(UriTemplate = "Endpoint/{param1}/{param2}")]
public void WillFail() { }
[WebGet(UriTemplate = "Endpoint/{param1}/{param2}")]
public void WillFail2(String param1) { }
}
}