Develop Reference

Wrong reference of Newtonsoft assembly for class library in another program

I have a class library in .NET Framework 4.7.2 and I use a reference to Newtonsoft.Json Version 12... something.
If I run the app as a windows application (there is a winform) everything works just fine. However, it is actually a class library that is being called by another program as a plugin. Inside that program I get however this error
Which translates basically to "couldn't find the Assembly...". There Version=12.0.0.0 is begin referenced and the dll in that particular folder (the plugin folder) says version 12.0.3.23909
I tried to clean the solution, delete every reference to newtonsoft I found etc. but the result is always identical. What am I missing?
Sorry if this question has been answered before, I searched dozens of previous questions, but I can't seem to understand what is going on appart from "redo everything", which doesn't work here.
UPDATE
The output bin is as follows
If I change the program to a windows application and run it by calling the exe, it works, but not via the other program where it should run as a plugin. Interestingly, the core dll is being opened and the baseform works, but not newtonsoft.

Change at least one of the versions. I mean:
Change the version of Newtonsoft of your class library to -> 12.0.3.23909 and then build the class library and use it as a plugin.
Or change the Newtonsoft version of your project to 12.0.0 and then use your class lib as a plugin inside it.
Or:
You can carry Newtonsoft (12.0.0) with your class library and load both of Newtonsft and your class library as a plugin. (this works too but you should be aware of Dll conflict between 12.0.0 and 12.0.3)

C# Do Roslyn work on Android (with Xamarin)?

I recently use Roslyn to compile and execute code at the runtime of a game application. Thank to some useful ressource such as this web site and Vendettamit answer, I manage to code a program on a C# Console Net Core project on window 10 which execute this code located in a txt file at the root of the application.
using System;
namespace Test15
{
public class Program
{
public static int Main()
{
System.Console.WriteLine("Hello World from external Dll !");
System.Console.WriteLine("And it work !");
return 10;
}
}
}
I'm not going to share code because it is really similar to Vendettamit answer, and this program work well on a C# Console Net Core project on window 10.
So next step, I try to make this program work with the C# Monogame Framework on a Android project which use Xamarin.
First problem : when trying to add the nugget package "Microsoft.CodeAnalysis" which seem necessary for Roslyn, I have the 2 following error :
Unable to resolve reference 'Humanizer', referenced by `Microsoft.CodeAnalysis.CSharp.Workspaces`.
Add NuGet package or assembly reference for 'Humanizer', or remove the reference to
'Microsoft.CodeAnalysis.CSharp.Workspaces'. Game2
Unable to resolve reference 'SQLitePCLRaw.core', referenced by `Microsoft.CodeAnalysis.Workspaces`.
Add NuGet package or assembly reference for 'SQLitePCLRaw.core', or remove the reference to
'Microsoft.CodeAnalysis.Workspaces'. Game2
(Translated from French)
When replacing the "Microsoft.CodeAnalysis" nugget package by "microsoft.CodeAnalysis.CSharp", both errors disappears.
However at the runtime, adding the MetadataReference don't work.
For instance in the Console project I use :
MetadataReference.CreateFromFile(typeof(object).GetTypeInfo().Assembly.Location);
To add a MetadataReference to mscorlib.dll, but on an Android project, it crash because typeof(object).GetTypeInfo().Assembly.Location return "mscorlib.dll" instead of somethings like "C:\Program Files\dotnet\shared\Microsoft.NETCore.App\3.1.9\System.Private.CoreLib.dll", because we are on Android I guess. (same with other MetadataReference )
So when calling the method CSharpCompilation.Create(), the "reference" argument is an array of null MetadataReference and it crash.
Based on what I read, I think (but I'm not sure) that Roslyn can't work on android because of the missing location of System.Object.
So can someone can confirm (or invalidate) if there is a way to work with Roslyn on Android ?
(Bonus point if you know some other way to compile/execute or "interpret" C# code on any device)
Thank for reading and stay safe.

How to run C# class library which is added to VB.NET existing solution?

Hi I have console application which is written in VB.NET. For this I added c# class library with existing solution. I wrote code in c# class library. Now when I try to run, it is going to VB.NET console application by default. I am not able to run my c# class library.
For clear understanding lets call VB.NET project as classVB and class library as classC#
I tired these methods to make it work :
1) Added classC# reference to my classVB project and made classVB as startup project. I used using statement also to refer to my classVB project as Using classVB. And I put break point in my classC#.But still it is pointing to classVB project
2) Tried to made classC# as startup project( Even I knew this doesn't gonna work). For this I am getting usual error which says "A project with an output Type of class library cannot be started directly."
3) Right click on solution and start up project option -> Single startup project and selected classVB.
But none of this is working. It is always pointing to my classVB project even after I put breakpoint on c#class library code.
Its the first time I am working on library class, so any help on this would be appreciated.

You can't directly run a class library. It is not executable. You can reference the code from it in your VB project, but a class library can never run by itself. To access a public method in your class library from VB, refer to it by Namespace.ClassName.MethodName.

Change the compilation output of the library to the same path where you added the reference in the VB.NET application. Generate the library and check the build is successful.
Do not forget to change the library class to configuration debug in the solution to generate the PDB file that will allow you debugging. Put a breakpoint and try again.

I can't reference my class library

I have a solution that contains two projects developed in visual studio 2012 express, and both targeting the .net framwork 4.5.
the first "Dao" project purpose is to take data from a database. and take these data to the second project as a dll library
the second project "UI" purpose is to display data coming from dll library
when i added reference to the second project and wrote using statement, I got the following error:
The type or namespace name 'Dao' could not be found (a using directive or an assembly reference missing?)
I tried to change the target of the two projects to .net framework 4.0 and .net framework 3.5 , but I got the same error.
I also add this piece of code to be sure that the target is change but I got true :
using System;
using Dao; // error
namespace Ui
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine(Type.GetType("System.Reflection.ReflectionContext", false) != null);
Console.ReadKey();
}
}
}
What do I need to do to fix the problem? Thanks a bunch.

You need to add a reference to your Dao assembly from your UI assembly. Right Click on References, Add Reference. In the Projects tab, select your Dao project and hit OK.

First things first:
Add a reference to Dao - in source explorer right click references->Add->projects tab.
Add a using statement at the top of your code something like using Dao;
Ensure Dao is a public class
This way your code will know to reference Dao, it is usually better to create a new instance of Dao:
Dao example = new Dao();
Then when calling Dao you would call example instead, so example.(name of method)

Create Project Dependency and Add Reference to Project still causes "The type or namespace name could not be found"

I have a solution in Visual Studio 2010 containing 6 projects (1 web application, 4 c# class libraries, 1 c# console application).
The console application is my test harness and use this to test external web services, output from methods from within my other libraries and general experimentation. This test console application has only one dependency on another project dependency, one of the C# libraries.
The referenced C# library is pretty simple:
namespace GowallaAPI
{
public class Gowalla
{
private static readonly ILog log = LogManager.GetLogger(typeof(Gowalla));
public SpotsInRadius GetGowallaSpotsInRadius(decimal lat, decimal lon, int radius) {
//snip
}
//other methods removed for brevity//
}
}
I have added to my console application a project reference:
And I've also right-clicked on References and selected Add Reference...
Then, I've gone to my console application and added;
using Gowalla;
Then hit build. I get this:
The type or namespace name 'Gowalla'
could not be found (are you missing a
using directive or an assembly
reference?)
I am completely baffled. I have:
Remove the dependencies completely (and then rebuilt with Gowalla references removed), and added them again.
I have removed the dependencies completely (like #1) and then added them as assemblies only (Add Reference...).
Checked that the target framework for both console application and class library is .NET 4.0 - they are.
Checked that all necessary items within the Gowalla class library are marked as Compile in the Build property.
Jiggled the build order of the project so that I am at least building the console application AFTER the library is built.
Done some shouting and swearing.
Given up and then returned.
Moved the Gowalla C# library out to its own project entirely and then referenced the assembly (like in 2).
Playing the having a constructor in Gowalla and not:
public Gowalla()
{
}
... and nothing has worked!
Can anyone see something obvious? Am I being utterly stupid? I have been on this for hours and I wonder quietly if this is a classic 'wood for the trees' moment...
Help appreciated.
EDIT 1: This is the Gowalla.dll exposed from Reflector:
ANSWER: After #gov's helpful suggestion to remove the GowallaAPI library and try and add something else I did that and started adding in the old code from the GowallaAPI library. Everything worked until I added:
private static readonly ILog log = LogManager.GetLogger(typeof(Gowalla));
log4net for some utterly bizarre reason kept throwing the build. Alas, after removing the line (the reference to log4net remains), the project built and worked perfectly thereafter. Thank you to #gov for setting me on the right path! :D

I had the exact same problem with log4net and it was resolved after changing target framework of the hosting project from ".NET Framework 4.0 Client Profile" to ".NET Framework 4.0"

I suggested him various things in the comments looks like one of them worked out.
#dooburt just forget about GowallaAPI and create a separate project like i say , sample.common and have a public class called utilities or so add that project here , just check a new project of type library and see whats the problem

Take a look at the .csproj XML, see if there is anything odd about the reference, one of these:
<Reference Include="Gowalla" ... />
<ProjectReference Include=".\path to\Gowalla.csproj" ... />

Have a look at the target framework of your class library and the test harness. I was having this error when the class library was set to .Net Framework 4 and the test harness was .Net Framework 4 Client Profile.