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Code Analyzer for C#

There is a newer version: 10.2.0.105762

Why is this an issue?
Marking a class with PartCreationPolicy(CreationPolicy.Shared), which is
part of Managed Extensibility Framework (MEF), means that a single, shared
instance of the exported object will be created. Therefore it doesn’t make sense to create new instances using the constructor and it will most likely
result in unexpected behaviours.
This rule raises an issue when a constructor of a class marked shared with a PartCreationPolicyAttribute is invoked.
How to fix it
Code examples
Noncompliant code example
[Export(typeof(IFooBar))]
[PartCreationPolicy(CreationPolicy.Shared)]
public class FooBar : IFooBar
{
}

public class Program
{
    public static void Main()
    {
        var fooBar = new FooBar(); // Noncompliant;
    }
}

Compliant solution
[Export(typeof(IFooBar))]
[PartCreationPolicy(CreationPolicy.Shared)]
public class FooBar : IFooBar
{
}

public class Program
{
    public static void Main()
    {
        var fooBar = serviceProvider.GetService<IFooBar>();
    }
}

Resources
Documentation

   PartCreationPolicy 
   CreationPolicy.Shared
  
   Managed Extensibility Framework