org.sonar.plugins.csharp.S4428.html Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of sonar-csharp-plugin Show documentation

Code Analyzer for C#

There is a newer version: 10.2.0.105762

Why is this an issue?
To customize the default behavior for an export in the Managed Extensibility
Framework (MEF), applying the PartCreationPolicyAttribute
is necessary. For the PartCreationPolicyAttribute
to be meaningful in the context of an export, the class must also be annotated with the ExportAttribute.
This rule raises an issue when a class is annotated with the PartCreationPolicyAttribute but not with the
ExportAttribute.
How to fix it
Code examples
Noncompliant code example
using System.ComponentModel.Composition;

[PartCreationPolicy(CreationPolicy.Any)] // Noncompliant
public class FooBar : IFooBar { }

Compliant solution
using System.ComponentModel.Composition;

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

Resources
Documentation

   Microsoft Learn - Managed Extensibility Framework (MEF) 
   Microsoft Learn - Attributed
  programming model overview (MEF) 
   Microsoft Learn - PartCreationPolicyAttribute
  Class 
   Microsoft Learn - ExportAttribute
  Class 
   Microsoft Learn - CreationPolicy
  Enum 

Articles & blog posts

   Stefan Henneken - MEF Part 1 – Fundamentals,
  Imports and Exports 
   Stefan Henneken - MEF Part 2 – Metadata and creation
  policies 
   Stefan Henneken - MEF Part 3 – Life cycle
  management and monitoring