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
    NSubstitute

    NSubstitute

    A friendly substitute for .NET mocking libraries

    NSubstitute is designed for Arrange-Act-Assert (AAA) testing, so you just need to arrange how it should work, then assert it received the calls you expected once you're done. Because you've got more important code to write than whether you need a mock or a stub. It is an attempt to satisfy our craving for a mocking library with a succinct syntax that helps us keep the focus on the intention of our tests, rather than on the configuration of our test doubles. We've tried to make the most frequently required operations obvious and easy to use, keeping less usual scenarios discoverable and accessible, and all the while maintaining as much natural language as possible. There are already some great mocking libraries around for .NET, so why create another? We found that for all their great features, none of the existing libraries had the succinct syntax we were craving — the code required to configure test doubles quickly obscured the intention behind our tests.
    Downloads: 2 This Week
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  • 2
    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: 2 This Week
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  • 3
    Spectre.Console

    Spectre.Console

    Library that makes it easier to create beautiful console applications

    Spectre.Console is a .NET library that enables the creation of rich, cross‑platform console applications. Heavily inspired by Python’s Rich library, it provides advanced styling, layout, and input capabilities for modern terminal UIs. Supports tables, grids, panels, and a Rich inspired markup language. Supports the most common SRG parameters when it comes to text styling such as bold, dim, italic, underline, strikethrough, and blinking text. Supports 3/4/8/24-bit colors in the terminal. The library will detect the capabilities of the current terminal and downgrade colors as needed. Written with unit testing in mind.
    Downloads: 2 This Week
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  • 4
    Veldrid

    Veldrid

    A low-level, portable graphics library for .NET

    Veldrid is a low-level, portable graphics library for .NET, providing a unified API over multiple graphics backends such as Direct3D, Vulkan, OpenGL, and Metal. It enables developers to write high-performance, cross-platform graphics applications without being tied to a specific graphics API. Veldrid is suitable for game development, simulations, and other applications requiring advanced graphics capabilities.
    Downloads: 2 This Week
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    eShopOnWeb

    eShopOnWeb

    Sample ASP.NET Core 8.0 reference application

    eShopOnWeb is Microsoft's .NET core sample reference application demonstrating monolithic web app architecture using Clean Architecture principles. It illustrates modern .NET patterns, organized across projects, and is designed for learning and as a starter template. The eShopOnWeb sample is related to the eShopOnContainers sample application which, in that case, focuses on a microservices/containers-based application architecture. However, eShopOnWeb is much simpler in regards to its current functionality and focuses on traditional Web Application Development with a single deployment.
    Downloads: 2 This Week
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  • 6
    iText Core/Community

    iText Core/Community

    iText for .NET is the .NET version of the iText library

    iText Core/Community (previously known as iTextSharp) is a high-performance, battle-tested library that allows you to create, adapt, inspect, and maintain PDF documents, allowing you to add PDF functionality to your software projects with ease. It is also available for Java. For more advanced examples, refer to our Knowledge Base or the main Examples repo. You can find C# equivalents to the Java Signing examples here, though the Java code is very similar since they have the same API. Some of the output PDF files will be incorrectly displayed by the GitHub previewer, so be sure to download them to see the correct results. The iText Suite builds on over a decade of lessons learned from iText 5 (and iTextSharp) development. The latest release of iText, version 8, is a simpler, more performant and extensible library that is ready to handle the increased challenges of today's document workflows, one add-on at a time.
    Downloads: 2 This Week
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  • 7
    OpenMCDF

    OpenMCDF

    Structured Storage .net component - pure C#

    OpenMCDF is a 100% .net / C# component that allows developers to manipulate Microsoft Compound Document File Format for OLE structured storage. It supports read/write operations on streams and storages and traversal of structures tree. Development and issue tracking has moved to github platform at https://github.com/ironfede/openmcdf
    Downloads: 9 This Week
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  • 8
    Fast Artificial Neural Network Library is a free open source neural network library, which implements multilayer artificial neural networks in C with support for both fully connected and sparsely connected networks. Cross-platform execution in both fixed and floating point are supported. It includes a framework for easy handling of training data sets. It is easy to use, versatile, well documented, and fast. Bindings to more than 15 programming languages are available. An easy to read introduction article and a reference manual accompanies the library with examples and recommendations on how to use the library. Several graphical user interfaces are also available for the library.
    Downloads: 9 This Week
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  • 9
    Cecil

    Cecil

    Cecil is a library to inspect, modify and create .NET programs

    Cecil is a library to inspect, modify and create .NET programs and libraries. Mono.Cecil is a library to generate and inspect programs and libraries in the ECMA CIL form. Analyze .NET binaries using a simple and powerful object model, without having to load assemblies to use Reflection. Modify .NET binaries, add new metadata structures and alter the IL code. Cecil has been around since 2004 and is widely used in the .NET community. If you're using Cecil, or depend on a framework, project, or product using it, please consider sponsoring Cecil. Cecil 0.10 beta 5 addresses a long standing issue: previously, a rewrite of native pdb files would lose some debugging information, including the list of namespaces that were used in methods (and thus breaking the expression evaluation) or the scopes in generators (for iterators or async methods).
    Downloads: 1 This Week
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  • 10
    ClearScript

    ClearScript

    A library for adding scripting to .NET applications

    ClearScript is a library that makes it easy to add scripting to your .NET applications. It currently supports JavaScript (via V8 and JScript) and VBScript. Simple usage; create a script engine, add your objects and/or types, run scripts. Support for several script engines: Google's V8, Microsoft's JScript and VBScript. Exposed resources require no modification, decoration, or special coding of any kind. Scripts get simple access to most of the features of exposed objects and types. Full support for generic types and methods, including C#-like type inference and explicit type arguments. Exposed .NET collections support native script iteration mechanisms. Scripts can invoke methods with output parameters, optional parameters, and parameter arrays. Support for exposing all the types defined in one or more assemblies in one step. Optional support for importing types and assemblies from script code.
    Downloads: 1 This Week
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  • 11
    CppSharp

    CppSharp

    Tools and libraries to glue C/C++ APIs to high-level languages

    CppSharp is a tool and set of libraries that facilitates the usage of native C/C++ code with the .NET ecosystem. It consumes C/C++ header and library files and generates the necessary glue code to surface the native API as a managed API. Such an API can be used to consume an existing native library in your managed code or add managed scripting support to a native codebase. The supported target languages at present are C# and C++/CLI. It can also be used as a library to parse native code into a syntax tree with a rich declaration and type information model. Generates the glue binding code from a syntax tree of the native code. Provides APIs for parsing of C/C++ source code into a syntax tree. Mirrors the Clang's C/C++ AST and type system classes in C# APIs.
    Downloads: 1 This Week
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  • 12
    Hymnal Xamarin

    Hymnal Xamarin

    New version of the adventist hymnal multi-platform and multi-language

    Hymnal Xamarin is an open-source Xamarin application for accessing hymnals, providing a simple and intuitive interface for worship.
    Downloads: 1 This Week
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  • 13
    XPL

    XPL

    Unity Post Processing Stack Library

    The XPL Library project is a collection of advanced post-processing effects designed for use in Unity projects. It provides a wide range of visual effects such as bloom, color grading, motion blur, and stylized filters, enabling developers to enhance the visual quality of their games. The library is built with performance in mind, ensuring that effects can be applied efficiently in real-time environments. It integrates seamlessly with Unity’s rendering pipeline, allowing developers to easily incorporate and customize effects. The project also includes shader implementations and configurable parameters, giving users fine control over visual output. It is particularly useful for achieving cinematic or stylized aesthetics in games. Overall, X-PostProcessing-Library offers a powerful toolkit for enhancing graphics in Unity applications.
    Downloads: 1 This Week
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  • 14
    sharpPDF is easy-to-use c# library to generate PDF on the fly. It allows to save pdf files or get binary streams in output(for example, usable in ASP.NET).
    Downloads: 9 This Week
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  • 15
    APTools
    APTools (Accelerate Programming Tools) is a .NET libraries that aim to provide common needed objects and functions and therefore accelerate programming. Its brings immutable collections, parameter validation, design patterns interfaces and more.
    Downloads: 18 This Week
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  • 16
    DSP Lab

    DSP Lab

    Digital Signal Processing Simulation

    DSP Lab is a digital signal processing simulation application created to simulate and visualize process of sampling and filtering analog signal using DSP system. This application is created to provide as a tool for educator and student to visualize and understand DSP system. Source code is available at https://payhip.com/b/9mPY
    Downloads: 12 This Week
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  • 17
    WebKit .NET
    WebKit .NET is a control library wrapper for WebKit written in C#. The aim is to make it easy for users to incorporate WebKit into their .NET applications.
    Downloads: 2 This Week
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  • 18
    Coronis SDK

    Coronis SDK

    Set of module for data processing of wireless device

    The goal is to create a leading “Set of software libraries for data processing of wireless device based on Coronis platform“. These libraries will run on all major platforms (embedded and desktop) and provide services for data processing through generic APIs. Keywords: Coronis, Wavenis, API, Plugin, Wireless, Waveport, Wavecard, Profile, Java, C, C++, C#
    Downloads: 3 This Week
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  • 19
    Simple Network Management Protocol (SNMP) .Net library written in C# (csharp). Implements protocol version 1, 2 and 3
    Downloads: 2 This Week
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  • 20
    Accord.NET Framework

    Accord.NET Framework

    Scientific computing, machine learning and computer vision for .NET

    The Accord.NET Framework provides machine learning, mathematics, statistics, computer vision, computer audition, and several scientific computing related methods and techniques to .NET. The project is compatible with the .NET Framework. NET Standard, .NET Core, and Mono.
    Downloads: 5 This Week
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  • 21
    AL-IV

    AL-IV

    ALFOUR Programming language. Simple, safe, power, multi-platform.

    A programming language AL-IV (ALFOUR) is a high-level imperative object oriented programming language with minimal introduction level, easy porting to any platform claiming a very high level of safety and stability, with a controllable level of code protection, high efficiency of an executable code, full independence from a target platform, minimal enter level.
    Downloads: 8 This Week
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  • 22
    NestProfessor Programmer Edition
    This is a SDK which can nest/layout the part/geometry/polygon on the material or sheet intelligently, you can get the best utilization of the materials, this SDK also support read/write DXF/DWG files and part-in-part nesting. New nesting lagorithm is implenmented, more good to support true shape part or material.
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    Downloads: 4 This Week
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  • 23

    OpenGL4Net

    Simple OpenGL 4.3 wrapper for .NET platform

    Feb. 2014: The project is still active; a new version with many changes is comming soon! NOTE: The Khronos group made a big shift in describing the OpenGL specification. Starting from OpenGL 4.4, the old .spec files are replaced by .xml which is great news for community, bad news for me and this project as it strongly depends on the old format. Currently I am working on the new version, but there's really a huge change, so please, be patient. I'd also would like to make the licensing clear (probably BSD). OpenGL4Net is a simple wrapper of OpenGL 4.3 for .NET platform. The main idea of the library is to keep the syntax as close as possible to the C style and on the other hand, provide some overloaded functions that simplifies the development of .NET application. The library also contains some helper classes to make a development really fast (e.g., class RenderContext for opening the OpenGL context; or class Program for loading, compiling and linking shaders)
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    Downloads: 4 This Week
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  • 24
    Object-oriented database

    Object-oriented database

    Object-Oriented Database in C# with PowerShell interface

    - Suitable for mobile apps, enterprise software in C#, data science tasks. - Can be easily used as a local database in C# application or used as database server. - Nested data structures supported. - PowerShell interface for interactive mode and scripting. - Available as cloud database on ENGITEX own cloud as well as for local deployment. See project Wiki for more.
    Downloads: 7 This Week
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  • 25
    Voikko

    Voikko

    Library of linguistic tools

    Voikko is a spell checking, grammar checking, morphological analysis and hyphenation system. Spell checkers are available for multiple languages, other features for Finnish only.
    Downloads: 7 This Week
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