.NET assembly created by Matlab NE Builder cannot be used from Matlab ("The type initializer for ... threw an exception")?

Initial intention (summary):

1. Call a .NET DLL from Matlab and analyze the results.

2. Add some Matlab algorithm to this DLL (i.e. call .NET assembly created from Matlab script by Builder NE)

3. Repeat step 1.

Resulting failure:

The type initializer for Namespace.<Class> threw an exception

Steps for simplified version of the test:

1. Create with deploytool a project Summator.prj (.NET assembly, class SumClass) wrapping a simple script, say:

function img = imagesum(img1, img2)
img = img1 + img2;

2. Build the project: the assemblies Summator.dll and SummatorNative.dll can be found now in C:\Users\MyName\Documents\MATLAB\Test.NET\Summator\distrib .

3. Try to load the assembly from Matlab:

myroot = 'C:\Users\MyName\Documents\MATLAB\Test.NET'
mypath=fullfile(myroot,'\Summator\distrib');
addpath(mypath);
asm = NET.addAssembly(fullfile(mypath,'Summator.dll'));
import Summator.*;
try
    mysummator = Summator.SumClass();
catch ex
    disp(ex); 
    disp(ex.ExceptionObject);
    disp(ex.ExceptionObject.TypeName);
    disp(ex.ExceptionObject.Message);
    disp(ex.ExceptionObject.InnerException);
    disp(ex.ExceptionObject.TargetSite);
    disp(ex.ExceptionObject.StackTrace);
    disp(ex.ExceptionObject.Source);
end

The result:

    myroot =

    C:\Users\MyName\Documents\MATLAB\Test.NET

    NET.NetException
    Package: NET

    Properties:
      ExceptionObject: [1x1 System.TypeInitializationException]
           identifier: 'MATLAB:NET:CLRException:CreateObject'
              message: 'Message: The type initializer for 'Summator.SumClass' threw an exception.
  Source: mscorlib
  HelpLink: '
                cause: {}
                stack: [1x1 struct]

    Methods, Superclasses

    System.TypeInitializationException handle
    Package: System

    Properties:
            TypeName: [1x1 System.String]
             Message: [1x1 System.String]
                Data: [1x1 System.Collections.ListDictionaryInternal]
      InnerException: [1x1 System.TypeInitializationException]
          TargetSite: [1x1 System.Reflection.RuntimeMethodInfo]
          StackTrace: [1x1 System.String]
            HelpLink: []
              Source: [1x1 System.String]
             HResult: -2146233036

    Methods, Events, Superclasses

Summator.SumClass

The type initializer for 'Summator.SumClass' threw an exception.

    System.TypeInitializationException handle
    Package: System

    Properties:
            TypeName: [1x1 System.String]
             Message: [1x1 System.String]
                Data: [1x1 System.Collections.ListDictionaryInternal]
      InnerException: [1x1 System.Exception]
          TargetSite: [1x1 System.Reflection.RuntimeConstructorInfo]
          StackTrace: [1x1 System.String]
            HelpLink: []
              Source: [1x1 System.String]
             HResult: -2146233036

    Methods, Events, Superclasses

    System.Reflection.RuntimeMethodInfo handle
    Package: System.Reflection

    Properties:
                            Name: [1x1 System.String]
                   DeclaringType: [1x1 System.RuntimeType]
                   ReflectedType: [1x1 System.RuntimeType]
                      MemberType: [1x1 System.Reflection.MemberTypes]
                   MetadataToken: 100667905
                          Module: [1x1 System.Reflection.RuntimeModule]
              IsSecurityCritical: 1
          IsSecuritySafeCritical: 1
           IsSecurityTransparent: 0
                    MethodHandle: [1x1 System.RuntimeMethodHandle]
                      Attributes: [1x1 System.Reflection.MethodAttributes]
               CallingConvention: [1x1 System.Reflection.CallingConventions]
                      ReturnType: [1x1 System.RuntimeType]
      ReturnTypeCustomAttributes: [1x1 System.Reflection.RuntimeParameterInfo]
                 ReturnParameter: [1x1 System.Reflection.RuntimeParameterInfo]
                 IsGenericMethod: 0
       IsGenericMethodDefinition: 0
       ContainsGenericParameters: 0
       MethodImplementationFlags: [1x1 System.Reflection.MethodImplAttributes]
                        IsPublic: 0
                       IsPrivate: 0
                        IsFamily: 0
                      IsAssembly: 1
             IsFamilyAndAssembly: 0
              IsFamilyOrAssembly: 0
                        IsStatic: 1
                         IsFinal: 0
                       IsVirtual: 0
                     IsHideBySig: 1
                      IsAbstract: 0
                   IsSpecialName: 0
                   IsConstructor: 0
                CustomAttributes: [1x1 System.Collections.ObjectModel.ReadOnlyCollection<System*Reflection*CustomAttributeData>]

    Methods, Events, Superclasses

     at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)

     at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)

     at System.Reflection.ConstructorInfo.Invoke(Object[] parameters)

     at dotnetcli.NETConstructor.invoke(NETConstructor* , COSClient* client, Int32* nlhs, COSValue* plhs, Int32 nrhs, COSValue* prhs)

mscorlib

The most important point: If I use the DLL from .NET application everything works, e.g.:

NETApp.ex -> NETAlgo.dll -> Summator.dll = Success

Matlab.exe -> Summator.dll = _Failure _(as shown above)

Matlab.exe -> NETAlgo.dll -> Summator.dll = Failure (same way)

Details (environment) :

A. MATLAB Version: 8.0.0.783 (R2012b) 32-bit

Operating System: Microsoft Windows 7 Version 6.1 (Build 7601: Service Pack 1) Java Version: Java 1.6.0_17-b04 with Sun Microsystems Inc. Java HotSpot™ Client VM mixed mode

B. .NET framework: v4.0.30319

[Yuri Shirman]

One more input: the same problem with this test

thepath = 'C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v80\toolbox\dotnetbuilder\bin\win32\v2.0';
addpath(thepath);
%addpath('C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v80\bin\win32');
asm = NET.addAssembly(fullfile(thepath,'MWArray.dll'));
import MathWorks.MATLAB.NET.Arrays.*
import MathWorks.MATLAB.NET.Utility.*
x = MathWorks.MATLAB.NET.Arrays.MWNumericArray(1,1);

[Yevgen Revtsov]

I am facing the same problem. Any updates?

[James Mithen]

I am also facing the same problem.

Answer 1

[Dhruvesh Patel]

This is a documented limitation. Please refer the following answer.

Is it possible to use the MATLAB .NET interface to load a MATLAB Builder NE generated .NET assembly?