Implementing IDisposable - Disposable Fields vs. Disposable Properties

Question

I was running VS2013's code analysis on one of my current projects, and came across "CA1001: Types that own disposable fields should be disposable." A simple example that generates the warning (presuming DisposableClass implements IDisposable) is:

class HasDisposableClassField
{
    private DisposableClass disposableClass;
}

However, converting the field variable to a property no longer generates the warning, even if the circumstance is that the property will be instantiated by the class:

class HasDisposableClassProperty
{
    private DisposableClass disposableClass { get; set; }
    public HasDisposableClassProperty()
    {
        disposableClass = new DisposableClass();
    }
}

In the first case it's clear that the class should implement the IDisposable pattern, and dispose of its disposableClass field appropriately. My question: is the lack of a warning for the second case a limitation of the code analysis tool? Should the class still implement IDisposable and dispose of the property, despite the lack of a warning?

Answer 1

Yes, the lack of a warning is a limitation of the analysis tool.

You should definitely still implement IDisposable and clean up after yourself assuming your IDisposable properties aren't being injected from elsewhere.

Answer 2

Yes; you still need to dispose it.

Putting something in a property does not magically dispose it for you.

The missing warning is a bug on Code Analysis (it ignores the backing field because it's compiler-generated)