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Code Analyzer for C#

There is a newer version: 10.2.0.105762

Why is this an issue?
This rule raises an issue when a disposable type contains fields of the following types and does not implement a finalizer:

   System.IntPtr 
   System.UIntPtr 
   System.Runtime.InteropService.HandleRef 

Noncompliant code example
using System;
using System.Runtime.InteropServices;

namespace MyLibrary
{
  public class Foo : IDisposable // Noncompliant: Doesn't have a finalizer
  {
    private IntPtr myResource;
    private bool disposed = false;

    protected virtual void Dispose(bool disposing)
    {
      if (!disposed)
      {
        // Dispose of resources held by this instance.
        FreeResource(myResource);
        disposed = true;

        // Suppress finalization of this disposed instance.
        if (disposing)
        {
          GC.SuppressFinalize(this);
        }
      }
    }

    public void Dispose() {
      Dispose(true);
    }
  }
}

Compliant solution
using System;
using System.Runtime.InteropServices;

namespace MyLibrary
{
  public class Foo : IDisposable
  {
    private IntPtr myResource;
    private bool disposed = false;

    protected virtual void Dispose(bool disposing)
    {
      if (!disposed)
      {
        // Dispose of resources held by this instance.
        FreeResource(myResource);
        disposed = true;

        // Suppress finalization of this disposed instance.
        if (disposing)
        {
          GC.SuppressFinalize(this);
        }
      }
    }

    ~Foo()
    {
      Dispose(false);
    }
  }
}

Resources

   Related: {rule:csharpsquid:S3881} - "IDisposable" should be implemented correctly