.CS File Extension

C# Source Code File

Developer Microsoft
4.3  |  375 Votes

What is a CS file?

A CS file is a source code file written in C# (pronounced "C Sharp"), an object-oriented programming language created by Microsoft for use with .NET Framework and .NET (successor to .NET Framework). It is used for developing a range of applications, from simple desktop programs to applications for distributed environments.

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Screenshot of a .cs file in Adobe Dreamweaver CC 2019
CS file open in Adobe Dreamweaver CC 2019

Developers utilize C# for building applications that run in the .NET ecosystem, which is a software framework that provides a standard method for building and deploying applications (primarily in Windows). The programming language is component-oriented, and some of its features include nullable types, exception handling, garbage collection, lambda expressions, asynchronous operations, and Language Integrated Query (LINQ) syntax. It also is flexible (through versioning) to ensure compatibility as technologies evolve.

Microsoft developed C# in 2000, and Ecma approved it as an international standard in 2002. It was originally released with .NET Framework 1.0 and included with Visual Studio .NET 2002.

Throughout the years, Microsoft has released numerous versions of C# with .NET Framework and Visual Studio. Some notable releases:

  • C# 2.0 - November 2005 - .NET Framework 2.0 and Visual Studio 2005
  • C# 3.0 - November 2007 - .NET Framework 2.0-3.5 and Visual Studio 2008
  • C# 4.0 - April 2010 - .NET Framework 4.0 and Visual Studio 2010
  • C# 5.0 - August 2012 - .NET Framework 4.5 and Visual Studio 2012 and 2013
  • C# 6.0 - July 2015 - .NET Framework 4.6 and Visual Studio 2015
  • C# 7.0 - March 2017 - .NET Framework 4.7 and Visual Studio 2017
  • C# 8.0 - September 2019 - .NET Core 3.0-3.1 and Visual Studio 2019 (16.3)
  • C# 9.0 - September 2020 - .NET 5.0 and Visual Studio 2019 (16.8)

NOTE: When C# programs are compiled, they can then be run by the Common Language Runtime (CLR) included with the .NET Framework.

How to open a CS file

You can open and edit CS files with Visual C#, a Microsoft Visual Studio component. You can also edit the files with various other source code editors that feature syntax highlighting, such as the cross-platform Microsoft Visual Studio Code.

CS files may be opened and edited with basic text editors, including Microsoft Notepad++ (bundled with Windows) or Apple TextEdit (bundled with macOS). However, plain text editors are not good options for editing the files since they do not support the syntax structure.

If you are looking to compile CS files, Mono is a common choice and is open source and cross-platform.

Open and view .CS files with File Viewer Plus.Free Download

Programs that open CS files

CLEO Custom Script

Developer Rockstar Games
4.2  |  127 Votes

Custom script written for CLEO 3, a third-party scripting engine for Grand Theft Auto: San Andreas (GTA SA); allows players to expand the capabilities of the game using custom functions called "opcodes;" may be created with Sanny Builder, a GTA mod utility.

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In order to use a CS file with GTA SA, it must be stored in the "game\CLEO" folder.

Programs that open CS files

ColorSchemer Studio Color Scheme

Developer CHROMAom
3.5  |  35 Votes

File created by ColorSchemer Studio, a program used for developing color palettes for websites, magazines, home decoration, and other target mediums; saves the user's color schemes, which often contain complementary colors that are matched with one another on the color spectrum.

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NOTE: CHROMAom ColorSchemer Studio has been discontinued.

Programs that open CS files

CHROMAom ColorSchemer Studio

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