Browse free open source C# Libraries and projects below. Use the toggles on the left to filter open source C# Libraries by OS, license, language, programming language, and project status.

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  • 1
    Pidgin

    Pidgin

    A lightweight and fast parsing library for C#

    Pidgin is a lightweight and fast parser combinator library for C#. It allows developers to construct parsers using a declarative approach, facilitating the creation of complex parsers without external tools.​
    Downloads: 0 This Week
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  • 2
    This is a Generic Plugin Mechanism for the .NET framework providing a quick implementation of a Plugin System for any .NET Application ( under the 2.0 or 3.5 versions ).
    Downloads: 0 This Week
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  • 3
    Polly

    Polly

    A .NET resilience and transient-fault-handling library for policies

    Polly is a .NET resilience and transient-fault-handling library that allows developers to express policies such as Retry, Circuit Breaker, Timeout, Bulkhead Isolation, and Fallback in a fluent and thread-safe manner. From version 6.0.1, Polly targets .NET Standard 1.1 and 2.0+. Today's cloud application, mobile, data-streaming, and IoT technologies all depend vitally on reliable connectivity. But underlying systems can fail, and networks are notoriously fickle, outages, latency, transient blips, spikes in load, all challenge 100% reliability. Polly helps you navigate the unreliable network. By providing resilience strategies in fluent-to-express policies such as Retry, WaitAndRetry, and CircuitBreaker, Polly can help you reduce fragility, and keep your systems and customers connected. Example usages are fault-tolerance for any distributed systems and inter-process calls, such as WCF, RESTful calls between microservices, calls to cloud services, Internet of Things connectivity, etc.
    Downloads: 0 This Week
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  • 4
    Console and library-based windows app for tagging of media files. Supports adding full tags, MusicBrainz tagging, and music fingerprinting.
    Downloads: 0 This Week
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  • 5
    A toolbox of .NET components that accelerate .NET application development.
    Downloads: 0 This Week
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  • 6
    PurpleBox

    PurpleBox

    Base-library for (WPF-) desktop applications

    This is a common base-library that powers (WPF-) desktop applications. Models: - Common Base-Class with INotifyPropertyChanged support - Undo/Redo Journal for Models View-Models: - Declarative Commands - View-Model to Model Synchronization It was built for Quality Spy and System Composer and can power similar applications.
    Downloads: 0 This Week
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  • 7
    qwtdotnet is a port of the popular qwt graphing toolkit to the .NET platform, relying on qt4dotnet.
    Downloads: 0 This Week
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  • 8
    QuadTree
    A generic type QuadTree implementation in C# for use with XNA. This QuadTree can store any object that implements the interface IHasRectangle. This provides a means of accessing objects in a virtual space very quickly. Development moved to: https://bitbucket.org/C3/quadtree/
    Downloads: 0 This Week
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  • 9
    Quantities.net is a physical quantities library for C#. It performs runtime checking for compatible dimensions in arithmetic operations. it separates the concepts of a dimensioned quantity and a unit, so that units are easily extensible.
    Downloads: 0 This Week
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  • 10

    Quorra

    Lua interpreter and API for .NET

    Quorra provides a multi-platform Lua API runtime and console for .NET applications.
    Downloads: 0 This Week
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  • 11
    RAMvader

    RAMvader

    A C# library which provides access to other processes' memory space.

    [ATTENTION] As of 2018-09-02 this project has been moved to GitHub and is now available in the link provided below: https://github.com/vinicius-ras/ramvader [DESCRIPTION] A .Net (C#) library which provides access to other processes' memory spaces.
    Downloads: 0 This Week
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  • 12
    Win32 dll frontend to ffmpeg and or tutorial on how to use ffmpeg
    Downloads: 0 This Week
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  • 13
    RSPbzip2
    This is bzip2/bzip3 compression/uncompression win32 and win64 dll, now with support to multi-threads
    Downloads: 0 This Week
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  • 14
    RSPchecksum

    RSPchecksum

    checksums rsp32, ds32 and ds64

    After 20/may/2026 this project only includes the rsp32, ds32 and ds64 checksums and developed and optimized in Linux
    Downloads: 0 This Week
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  • 15
    RSPencdll

    RSPencdll

    Updated to recommend the AES 256 CTR Galois mode

    Updated to recommend the AES 256 CTR Galois mode The past versions was using a method based in the 2001 wikipedia information, and in 2007 the Galois mode was applied then now we recommed on the Galois mode, ok
    Downloads: 0 This Week
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  • 16
    Win32/Win64 dll to format removable drives or hds
    Downloads: 0 This Week
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  • 17
    RSPmfce
    Win32/Win64 DLL to compress memory or files using zlib, bzip2, xz or LZO , the integrity check is provided by crc32
    Downloads: 0 This Week
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  • 18
    simple win32 dll to control the system mixer, it will be updated at 2021/04/09 before 22:00 PM
    Downloads: 0 This Week
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  • 19
    RSPmplayer
    simple .Net framework component to play media files using DirectShow, this project was supersede by the project http://rsppmp3.sourceforge.net/ , it is a standalone audio and video player capable of playing all major formats, no additional codecs required, please use it instead
    Downloads: 0 This Week
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  • 20
    RainDoll aims to be an implementation of a symmetric-encryption utility for desktop users written in C#/.NET and Windows Forms with two goals: security and simplicity. It uses cryptographic standards for security, and has a smart, compact interface.
    Downloads: 0 This Week
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  • 21
    Czech - Knihovna umoznujici jednoduche stahovani ze servru rapidshare.com, funguje pouze pri pouziti premium account. Je zapotrebi pouze dodelat nejake GUI Englis - Dll for easy download from rapidshare.com. Works only with premium account.
    Downloads: 0 This Week
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  • 22
    It's an infrastructure helps engineers to develop enterprise software solutions in Microsoft .NET easily and productively which consists of an extendable and maintainable web system architecture with a suite of generic business model, APIs and servi
    Downloads: 0 This Week
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  • 23

    ReCaptcha plugin for Kooboo CMS

    ReCaptcha Validator Plugin for Kooboo CMS for add content or send mail

    ReCaptcha Validator Plugin for Kooboo CMS for adding content or sending feedback e-mail
    Downloads: 0 This Week
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  • 24
    Refit

    Refit

    The automatic type-safe REST library for .NET Core, Xamarin and .NET.

    Refit is a library heavily inspired by Square’s Retrofit library, and it turns your REST API into a live interface. Refit currently supports the following platforms and any .NET Standard 2.0 target. Every method must have an HTTP attribute that provides the request method and relative URL. There are six built-in annotations: Get, Post, Put, Delete, Patch and Head. The relative URL of the resource is specified in the annotation. A request URL can be updated dynamically using replacement blocks and parameters on the method. A replacement block is an alphanumeric string surrounded by { and }. Parameters that are not specified as a URL substitution will automatically be used as query parameters. This is different than Retrofit, where all parameters must be explicitly specified. Round-tripping route parameter syntax: Forward slashes aren't encoded when using a double-asterisk (**) catch-all parameter syntax.
    Downloads: 0 This Week
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  • 25
    RegistryFilterExample

    RegistryFilterExample

    Registry Filter Driver SDK

    The EaseFilter Registry Filter Driver SDK is a powerful, kernel-mode development toolkit designed to help developers monitor, control, and protect Windows registry operations in real time. It enables the development of robust security, compliance, and system integrity solutions by intercepting and managing registry access before it reaches the Windows registry subsystem. The SDK allows your application to receive notifications before any registry operation is processed by the Windows Configuration Manager. By registering a RegistryCallback routine, your application can detect: Registry key creation, deletion, renaming Registry value changes Query operations
    Downloads: 0 This Week
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