Question

I’ve made a c# class that I’m trying to run in PowerShell with add-Type.
I have a few of my own assemblies referenced and some from .net4. I’m using my own PowerShell host because the assemblies I’m referencing are made on the .net4 framework and the PowerShell Console doesn’t support that yet.

Here is a sample of the script that i’m trying to run:

$Source = @"
using System;
using System.Collections;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using MyOwn.Components.Utilities;
using MyOwn.Components;
using MyOwn.Entities;

public class ComponentSubtypeMustMatchTemplate
{

    public static Guid ProblemId
    {
        get { return new Guid("{527DF518-6E91-44e1-B1E4-98E0599CB6B2}"); }
    }

    public static ProblemCollection Validate()
    {

 SoftwareStructureEntityContainer softwareEntityStructure = new SoftwareStructureEntityContainer();

        if (softwareEntityStructure == null)
        {
            throw new ArgumentNullException("softwareStructure");
        }

        ProblemCollection problems = new ProblemCollection();

        foreach (var productDependency in softwareEntityStructure.ProductDependencies)
        {......

        return problems;
    }
}
"@

$refs = @("d:\Projects\MyOwn\bin\MyOwn.Components.dll",
"d:\Projects\MyOwn\bin\MyOwn.Entities.dll",
"d:\Projects\MyOwn\bin\MyOwn.OperationalManagement.dll",
"c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Core.dll",
"c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Data.Entity.dll",
"c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Data.dll")

Add-Type -ReferencedAssemblies $refs -TypeDefinition $Source


$MyProblemCollection = new-Object ComponentSubtypeMustMatchTemplate
$MyProblemCollection.Validate()

Now when i run this I get this error:

{“Method invocation failed because [ComponentSubtypeMustMatchTemplate] doesn’t contain a method named ‘Validate’.”}

Ive also tried the last bit in different ways (found many different examples on how to do this) but they all seem to give the same error. I really have no idea how to get this working, and i can’t seem to find any example’s on something similar.

On a second note(for when i get this fixed) I was wondering if it was possible to be able to just load the .cs file instead of putting the c# code in the script. would be a better read and more maintainable.

Ive tried to see if I can see the methods with Get-Member -static like this:

$MyProblemCollection = New-Object ComponentSubtypeMustMatchTemplate
$MyProblemCollection | Get-Member -Static

And it does see the method there:

   TypeName: ComponentSubtypeMustMatchTemplate

Name            MemberType Definition                                           
----            ---------- ----------                                           
Equals          Method     static bool Equals(System.Object objA, System.Obje...
ReferenceEquals Method     static bool ReferenceEquals(System.Object objA, Sy...
Validate        Method     static MyOwn.ComponentSubtypeMustMatchTemplate...  <--
ProblemId       Property   static System.Guid ProblemId {get;}         

So why doesn’t it work!?

---

@Philip
in my script it doesn’t really matter if its static or non static cause it will always just be run once and the results will be used my program. But strange thing is it does seem to work if i use the static syntax (except for that i get no results at all) and if i use the non-static syntax i’ll get the same error. I also tried the script in an other PowerShell console i found on the interwebs, and there i get an entirely different error :

 PS C:\temp.
ps1
The following exception occurred while retrieving member "Validate": "Could not
 load file or assembly 'MyOwn.Entit
ies, Version=1.0.0.0, Culture=neutral, PublicKeyToken=fc80acb30cba5fab' or one
of its dependencies. The system cannot find the file specified."
At D:\Projects\temp.ps1:145 char:30
+ $MyProblemCollection.Validate <<<< ()
    + CategoryInfo          : NotSpecified: (:) [], ExtendedTypeSystemExceptio
   n
    + FullyQualifiedErrorId : CatchFromBaseGetMember

hmm nvm, it spontaneously worked! strange BUT i’m happy! =)

Answer 1

Your method is static, but you are trying to call it via an instance.

$MyProblemCollection = new-Object ComponentSubtypeMustMatchTemplate

Creates a new instance of ComponentSubtypeMustMatchTemplate.

$MyProblemCollection.Validate()

Calls the instance method named Validate on the object referenced by $MyProblemCollection. However, since there is no instance method named Validate, the call fails.

You can either make the methods non-static (which you would do if they were going to keep state in the object), or you can use a different powershell syntax used to call a static method:

$result = [ComponentSubtypeMustMatchTemplate]::Validate()

Remember ( if you keep these static ) that setting a static property means anything querying that property in the same process will get that value. If you are holding state, then I would advise removing the static from each declaration.