Question

I want to use using statement purely for scope management. Can I omit holding an explicit reference to the underlying object that implements IDisposable?

For example, giving this declaraions:

class ITransactionScope : IDisposable {}
class TransactionGuard : ITransactionScope {...}

class DbContext
{
    public IDisposable ITransactionScope()
    {
        return new TransactionGuard();
    } 
}

Can I do the following:

void main()
{
    var dbContext = new DbContext();

    using (dbContext.TransactionScope())
    {
        // the guard is not accessed here
    }
}

Is TransactionGuard instance alive during using statement?

Answer 1

I want to use the using statement purely for scope management.

You should use the using statement for what it is designed for: disposing an unmanaged resource in a timely manner. If that’s not what you’re using using for, you’re probably doing something wrong.

Can I omit holding an explicit reference to the underlying object that implements IDisposable?

As another answer pointed out: you already typed the code in; you could have simply tried it.

Yes, you can do that. The compiler will create an invisible local variable for you and call Dispose on it.

I recommend that if you have further questions about the usage of using that you read section 8.13 of the C# 4 specification.