ConcurrentPriorityQueue 1.0.0

.NET Standard 2.0
There is a newer version of this package available.
See the version list below for details.
dotnet add package ConcurrentPriorityQueue --version 1.0.0
NuGet\Install-Package ConcurrentPriorityQueue -Version 1.0.0
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="ConcurrentPriorityQueue" Version="1.0.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add ConcurrentPriorityQueue --version 1.0.0
#r "nuget: ConcurrentPriorityQueue, 1.0.0"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
// Install ConcurrentPriorityQueue as a Cake Addin
#addin nuget:?package=ConcurrentPriorityQueue&version=1.0.0

// Install ConcurrentPriorityQueue as a Cake Tool
#tool nuget:?package=ConcurrentPriorityQueue&version=1.0.0

ConcurrentPriorityQueue Build Status Nuget

A thread-safe generic first in first out (FIFO) collection with support for priority queuing.



  1. Thread-Safe.
  2. Manages items according to a First in first out policy and priority on top of that.
  3. Implements IProducerConsumerCollection<T> interface.
  4. Extends to a BlockingCollection<T>.


Items in the collection must implement the generic interface IHavePriority<T> where T: implements IEquatable<T>, IComparable<T> and also overrides Object.GetHashCode():

// Simplest implementation of IHavePriority<T>
public class SomeClass : IHavePriority<int> {
    int Priority {get; set;}

Simple flow for creating a Priority-By-Integer queue and adding an item:

// Create a new prioritized item.
var itemWithPriority = new SomeClass { Priority = 0 };

// Initialize an unbounded priority-by-integer queue.
var priorityQueue = new ConcurrentPriorityQueue<IHavePriority<int>, int>();

// Enqueue item and handle result.
Result result = priorityQueue.Enqueue(itemWithPriority);

Use the ConcurrentPriorityByIntegerQueue implementation to simplify the above example:

var priorityQueue = new ConcurrentPriorityByIntegerQueue<IHavePriority<int>>();

Consume items by priority/first-in-first-out policy, using Dequeue() and Peek():

// Lower value -> Higher priority.
var item1 = new SomeClass { Priority = 1 };
var item2 = new SomeClass { Priority = 0 };
var item3 = new SomeClass { Priority = 0 };


var result = priority.Dequeue(); // item2
var result = priority.Dequeue(); // item3
var result = priority.Dequeue(); // item1

Iterating over the collection will yield items according to their priority and position (FIFO):

var item1 = new SomeClass { Priority = 1 };
var item2 = new SomeClass { Priority = 0 };
var item3 = new SomeClass { Priority = 0 };


foreach(var item in priorityQueue) {
    // Iteration 1 -> item2
    // Iteration 2 -> item3
    // Iteration 3 -> item1

ConcurrentPriorityQueue supports Generic Priorities.

Implement your own Business Priority object and configure the queue to handle it:

// TimeToProcess class implements IEquatable<T>, IComparable<T> and overrides Object.GetHashCode().
public class TimeToProcess : IEquatable<TimeToProcess>, IComparable<TimeToProcess> {		
    public decimal TimeInMilliseconds { get; set;}

    public int CompareTo(TimeToProcess other) =>

    public bool Equals(TimeToProcess other) =>

    public override int GetHashCode() => TimeInMilliseconds.GetHashCode();
// BusinessPriorityItem implements IHavePriority<T>
public class BusinessPriorityItem : IHavePriority<TimeToProcess> {
    TimeToProcess Priority {get; set;}
// Create a new prioritized item.
var item = new BusinessPriorityItem { Priority = new TimeToProcess { TimeInMilliseconds = 0.25M } };

// Initialize an unbounded priority-by-TimeToProcess queue.
var priorityQueue = new ConcurrentPriorityQueue<IHavePriority<TimeToProcess>, TimeToProcess>();

// Enqueue item and handle result.
Result result = priorityQueue.Enqueue(item);

ConcurrentPriorityQueue<T> can be bounded to a fixed amount of priorities:

// Create a bounded ConcurrentPriorityQueue to support a fixed amount of priorities.
var maxAmountOfPriorities = 2;
var priorityQueue = new ConcurrentPriorityByIntegerQueue<IHavePriority<int>>(maxAmountOfPriorities);

Result result = PriorityQueue.Enqueue(new SomeClass {Priority = 0}); // result.OK
Result result = PriorityQueue.Enqueue(new SomeClass {Priority = 1}); // result.OK
Result result = PriorityQueue.Enqueue(new SomeClass {Priority = 2}); // result.Fail -> Queue supports [0, 1]
Result result = PriorityQueue.Enqueue(new SomeClass {Priority = 0}); // result.OK

ConcurrentPriorityQueue<T> can be extended to a BlockingCollection<T> using the ToBlockingCollection<T> extension method:

var blockingPriorityQueue = new ConcurrentPriorityByIntegerQueue<IHavePriority<int>>()

foreach(var item in blockingPriorityQueue.GetConsumingEnumerable()) {
    // Do something...
    // Blocks until signaled on completion.

Additional information and resources:

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 was computed.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed. 
.NET Core netcoreapp2.0 was computed.  netcoreapp2.1 was computed.  netcoreapp2.2 was computed.  netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.0 is compatible.  netstandard2.1 was computed. 
.NET Framework net461 was computed.  net462 was computed.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen40 was computed.  tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
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NuGet packages

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一款优雅的UWP文件管理器 | An elegant UWP Explorer
Version Downloads Last updated
2.1.0 4,470 2/1/2023
2.0.0 261 1/17/2023
1.0.0 4,836 7/27/2019