Thread Safe Concurrent Collection in C#

Push: Add item at top of ConcurrentStack.

PushRange: Tries to add multiple items at top of ConcurrentStack.

TryPeek: Tries to return last item from ConcurrentStack.

TryPop: Tries to pop and return last item from ConcurrentStack.

ConcurrentQueue<T>: This is thread-safe first-in-first-out collection.

Difference between Queue and ConcurrentQueue

Sr. No	Queue<T>	ConcurrentQueue<T>
1	Not thread-safe	Thread-safe
2	Queue has Enqueue and Dequeue methods	ConcurrentQueue has Enqueue and TryDequeue methods
3	Can add single item at a time.	Can add multiple item at a time.
4	Can remove single item at a time	Can remove multiple item at a time.

Enqueue: Add item to end of ConcurrentQueue.

TryDequeue: Tries to remove and return first item from ConcurrentQueue.

TryPeek: Return first item from ConcurrentQueue.

BlockingCollection<T>

This collection is thread-safe for adding and removing data. You can set maximum upper limit to add items in this collection. Removing an item from the collection can be blocked until item becomes available.

Add: Add item into BlockingCollection.

Take: Removes item from BlockingCollection .

TryAdd: Tries to add item into BlockingCollection.

TryTake: Tries to remove item from BlockingCollection.

ConcurrentBag<T>

ConcurrentBag is thread-safe collection. This collection is like just at bag or heap of objects. It has not ordering and it allow duplicate items.

ConCurrentBag has mainly three methods.

Add: Add item into ConcurrentBag collection.

TryTake: Tries to remove and return item from ConcurrentBag.

TryPeek: Tries to return item from ConcurrentBag.

ConcurrentDictionary<TKey,T>

Concurrent dictionary is thread-safe collection. It is used to store key-value pair in multi-threaded environment.

Add: Add item into concurrent dictionary.

Remove: Remove item from concurrent dictionary.

Update: Update existing item in concurrent dictionary.

TryUpdate: This method check whether item is exist or not before update.

AddOrUpdate: This method add item into concurrent dictionary if that object does not exist.

GetOrAdd: This method return current value in dictionary if it exist otherwise add as new value.

Read more articles on Multithreading:

• Introduction to Multithreading Part 2
• Threading Simplified: Part 8 (Synchronization Basics and Thread Blocking)