var collection = new BlockingCollection<int>(5);
var random = new Random();
var producerTask = Task.Run(() => {
for(int item=1; item<=10; item++)
{
collection.Add(item);
Console.WriteLine("Produced: " + item);
Thread.Sleep(random.Next(10,1000));
}
collection.CompleteAdding();
Console.WriteLine("Producer completed!");
});
It is worth noting that if you do not call collection.CompleteAdding();
, you are able to keep adding to the collection even if your consumer task is running. Just call collection.CompleteAdding();
when you are sure there are no more additions. This functionality can be used to make a Multiple Producer to a Single Consumer pattern where you have multiple sources feeding items into the BlockingCollection and a single consumer pulling items out and doing something with them. If your BlockingCollection is empty before you call complete adding, the Enumerable from collection.GetConsumingEnumerable()
will block until a new item is added to the collection or BlockingCollection.CompleteAdding(); is called and the queue is empty.
var consumerTask = Task.Run(() => {
foreach(var item in collection.GetConsumingEnumerable())
{
Console.WriteLine("Consumed: " + item);
Thread.Sleep(random.Next(10,1000));
}
Console.WriteLine("Consumer completed!");
});
Task.WaitAll(producerTask, consumerTask);
Console.WriteLine("Everything completed!");