vb.net calling a c# method is giving errors

Question

I am trying to access c# method from a vb.net project.

The c# project has the following code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using MeF.Client;

public class LoginClass
{
    // lines of code that are giving errors  (when commented there’s no error)
    private ServiceContext context = new ServiceContext();
    public string etin;
    public string appSysId;

    static void Main(string[] args)   
    { 
        LoginClass.CreateServiceContext();
    }

    //bla, bla, bla
}

---

The vb.net project has this:

Imports AimEFileCore

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim Process As New AimEFileCore.LoginClass
        Process.CreateServiceContext()
    End Sub

When running the code I get the following error

System.IO.FileNotFoundException: 'Could not load file or assembly 'MeFWCFClient, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified

A Mef dll is referenced!

As soon as I comment the three lines above, it works like a charm.

Answer 1

I believe you need to go to Project Properties, References and check whether you have there a correct reference for referenced MeFWCFClient (a dll). You can add it within this dialogue, you might be able to use Nuget, or simply copy it to binary folder.

Answer 2

It looks like the method you are calling is static. Have you tried this in vb.net?

AimEFileCore.LoginClass.CreateServiceContext()

you are instantiating LoginClass but there are no public methods defined - at least not in the code you are showing, so I've assumed it contains this:

public static void CreateServiceContext()
{
 ...
}

as that's what the C# code would suggest.

Answer 3

using MeF.Client;

Thats the culprit. Reference that DLL in your project.

Then on top add:

Imports MeF.Client