how to access the underlying default concurrent queue of a blocking collection

Question

I have multiple producers and a single consumer. However if there is something in the queue that is not yet consumed a producer should not queue it again. (unique no duplica

Answer 1

I would suggest implementing your operations with lock so that you don't read and write the item in a way that corrupts it, making them atomic. For example, with any IEnumerable:

object bcLocker = new object();

// ...

lock (bcLocker)
{
    bool foundTheItem = false;
    foreach (someClass nextItem in myBlockingColl)
    {
        if (nextItem.Equals(item))
        {
            foundTheItem = true;
            break;
        }
    }
    if (foundTheItem == false)
    {
        // Add here
    }
}