C# Versions

This article provides a history of each major release of the C# language (from Wiki and Microsoft).

C# Versions from Wiki
 

Version	Date	.NET	Visual Studio
C# 1.0	January 2002	.NET Framework 1.0	Visual Studio .NET 2002
C# 1.1 C# 1.2	April 2003	.NET Framework 1.1	Visual Studio .NET 2003
C# 2.0	November 2005	.NET Framework 2.0 .NET Framework 3.0	Visual Studio 2005 Visual Studio 2008
C# 3.0	November 2007	.NET Framework 2.0 (Except LINQ) .NET Framework 3.0 (Except LINQ) .NET Framework 3.5	Visual Studio 2008
C# 4.0	April 2010	.NET Framework 4	Visual Studio 2010
C# 5.0	August 2012	.NET Framework 4.5	Visual Studio 2012 Visual Studio 2013
C# 6.0	July 2015	.NET Framework 4.6 .NET Core 1.0 .NET Core 1.1	Visual Studio 2015
C# 7.0	March 2017	.NET Framework 4.7	Visual Studio 2017 version 15.0
C# 7.1	August 2017	.NET Core 2.0	Visual Studio 2017 version 15.3
C# 7.2	November 2017	Visual Studio 2017 version 15.5
C# 7.3	May 2018	.NET Core 2.1 .NET Core 2.2 .NET Framework 4.8	Visual Studio 2017 version 15.7
C# 8.0	September 2019	.NET Core 3.0 .NET Core 3.1	Visual Studio 2019 version 16.3
C# 9.0	November 2020	.NET 5.0	Visual Studio 2019 version 16.8
C# 10.0	November 2021	.NET 6.0 .NET 6.1	Visual Studio 2022version 17.0
C# 11.0	November 2022	.NET 7	Visual Studio 2022

C# Version History

C# was first introduced with .NET Framework 1.0 in the year 2002 and evolved much since then. The following table lists important features introduced in each version of C#.

Version	.NET Framework	Visual Studio	Important Features
C# 1.0	.NET Framework 1.0/1.1	Visual Studio .NET 2002	Basic features
C# 2.0	.NET Framework 2.0	Visual Studio 2005	Generics Partial types Anonymous methods Iterators Nullable types Private setters (properties) Method group conversions (delegates) Covariance and Contra-variance Static classes
C# 3.0	.NET Framework 3.0/3.5	Visual Studio 2008	Implicitly typed local variables Object and collection initializers Auto-Implemented properties Anonymous types Extension methods Query expressions Lambda expressions Expression trees Partial Methods
C# 4.0	.NET Framework 4.0	Visual Studio 2010	Dynamic binding (late binding) Named and optional arguments Generic co- and contravariance Embedded interop types
C# 5.0	.NET Framework 4.5	Visual Studio 2012/2013	Async features Caller information
C# 6.0	.NET Framework 4.6	Visual Studio 2013/2015	Expression Bodied Methods Auto-property initializer name of Expression Primary constructor Await in catch block Exception Filter String Interpolation
C# 7.0	.NET Core 2.0	Visual Studio 2017	out variables Tuples Discards Pattern Matching Local functions Generalized async return types
C# 8.0	.NET Core 3.0	Visual Studio 2019	Readonly members Default interface methods Using declarations Static local functions Disposable ref structs Nullable reference types
C# 9.0	.NET 5.0	Visual Studio 2019	Records Init-only properties Top-level statements Init accessors and read-only fields With-expressions Value-based equality
C# 10.0	.NET 6.0	Visual Studio 2022	Record structs Global use directives File-scoped namespace declaration Extended Proptery Patterns Null Parameter Checking Constant interpolated strings

The history of C# from MS

C# version 1.0

When you go back and look, C# version 1.0, was released with Visual Studio .NET 2002. The major features of C# 1.0 included.

• Classes
• Structs
• Interfaces
• Events
• Properties
• Delegates
• Operators and expressions
• Statements
• Attributes

C# version 1.2

C# version 1.2 shipped with Visual Studio .NET 2003. It contained a few small enhancements to the language. Most notable is that starting with this version, the code generated in a for each loop called Dispose on an IEnumerator when that IEnumerator implemented IDisposable.

C# version 2.0

Now things start to get interesting. Let's take a look at some major features of C# 2.0, released in 2005, along with Visual Studio 2005.

• Generics
• Partial types
• Anonymous methods
• Nullable value types
• Iterators
• Covariance and contravariance

Other C# 2.0 features added capabilities to existing features.

• Getter/setter separate accessibility
• Method group conversions (delegates)
• Static classes
• Delegate inference

C# version 3.0

C# version 3.0 came in late 2007, along with Visual Studio 2008, though the full boat of language features would come with .NET Framework version 3.5. This version marked a major change in the growth of C#. It established C# as a truly formidable programming language. Let's take a look at some major features in this version.

• Auto-implemented properties
• Anonymous types
• Query expressions
• Lambda expressions
• Expression trees
• Extension methods
• Implicitly typed local variables
• Partial methods
• Object and collection initializers

C# version 4.0

C# version 4.0, released with Visual Studio 2010. The next version did introduce some interesting new features.

• Dynamic binding
• Named/optional arguments
• Generic covariant and contravariant
• Embedded interop types

C# version 5.0

C# version 5.0, released with Visual Studio 2012, was a focused version of the language.The asyncand await model for asynchronous programming. Here is the list of the major features.

• Asynchronous members
• Caller info attributes

See Also

• Code Project: Caller Info Attributes in C# 5.0

C# version 6.0

With versions 3.0 and 5.0, C# had added major new features in an object-oriented language. With version 6.0, released with Visual Studio 2015. Here are some of them:

• Static imports
• Exception filters
• Auto-property initializers
• Expression-bodied members
• Null propagator
• String interpolation
• name of operator

Other new features include

• Index initializers
• Await in catch/finally blocks
• Default values for getter-only properties

C# version 7.0

C# version 7.0 was released with Visual Studio 2017. Here are some of the new features:

• Out variables
• Tuples and deconstruction
• Pattern matching
• Local functions
• Expanded expression-bodied members
• Ref locals and returns

Other features included

• Discards
• Binary Literals and Digit Separators
• Throw expressions

C# version 7.1

C# started releasing point releases with C# 7.1. This version added the language version selection configuration element, three new language features, and new compiler behavior.

The new language features in this release are

• async main method
  • The entry point for an application can have the async modifier.
• default literal expressions
  • You can use default literal expressions in default value expressions when the target type can be inferred.
• Inferred tuple element names
  • The names of tuple elements can be inferred from tuple initialization in many cases.
• Pattern matching on generic type parameters
  • You can use pattern match expressions on variables whose type is a generic type parameter.

Finally, the compiler has two options -refute and -refonly that control reference assembly generation.

C# version 7.2

C# 7.2 added several small language features

• Techniques for writing safe efficient code
  • A combination of syntax improvements that enable working with value types using reference semantics.
• Non-trailing named arguments
  • Named arguments can be followed by positional arguments.
• Leading underscores in numeric literals
  • Numeric literals can now have leading underscores before any printed digits.
• private protected access modifier
  • The private protected access modifier enables access for derived classes in the same assembly.
• Conditional ref expressions
  • The result of a conditional expression (?:) can now be a reference.

C# version 7.3

There are two main themes to the C# 7.3 release. The following new features support the theme of better performance for safe code.

• You can access fixed fields without pinning.
• You can reassign ref local variables.
• You can use initializers on stackable arrays.
• You can use fixed statements with any type that supports a pattern.
• You can use additional generic constraints.

The following enhancements were made to existing features

• You can test == and != with tuple types.
• You can use expression variables in more locations.
• You may attach attributes to the backing field of auto-implemented properties.
• Method resolution when arguments differ by it has been improved.
• Overload resolution now has fewer ambiguous cases.

The new compiler options are

• -publicsign to enable Open Source Software (OSS) signing of assemblies.
• -pathmap to provide a mapping for source directories.

What's new in C# 8.0

• 04/07/2020

C# 8.0 adds the following features and enhancements to the C# language

• Readonly members
• Default interface methods
• Pattern matching enhancements
  • Switch expressions
  • Property patterns
  • Tuple patterns
  • Positional patterns
• Using declarations
• Static local functions
• Disposable ref structs
• Nullable reference types
• Asynchronous streams
• Asynchronous disposable
• Indices and ranges
• Null-coalescing assignment
• Unmanaged constructed types
• Stackalloc in nested expressions
• Enhancement of interpolated verbatim strings

C# 8.0 is supported on .NET Core 3. x and .NET Standard 2.1. For more information, see C# language versioning.

What's new in C# 9.0

• 04/07/2021

C# 9.0 adds the following features and enhancements to the C# language

• Records
• Init only setters
• Top-level statements
• Pattern matching enhancements
• Performance and interop
  • Native-sized integers
  • Function pointers
  • Suppress emitting local flag
• Fit and finish features
  • Target-typed new expressions
  • static anonymous functions
  • Target-typed conditional expressions
  • Covariant return types
  • Extension GetEnumerator support for for-each loops
  • Lambda discard parameters
  • Attributes on local functions
• Support for code generators
  • Module initializers
  • New features for partial methods

C# 9.0 is supported on .NET 5. For more information, see C# language versioning.

What's new in C# 10

• 11/29/2022

C# 10 adds the following features and enhancements to the C# language

• Record structs
• Improvements in structure types
• Interpolated string handlers
• global use directives
• File-scoped namespace declaration
• Extended property patterns
• Improvements in lambda expressions
• Allowconstinterpolated strings
• Record types can sealToString()
• Improved definite assignment
• Allow both assignment and declaration in the same deconstruction
• AllowAsyncMethodBuilderattribute on methods
• CallerArgumentExpression attribute
• Enhanced#linepragma
• Warning wave 6

C# 10 is supported on.NET 6. For more information, seeC# language versioning.

What's new in C# 11

• 11/30/2022

The following features were added in C# 11

• Raw string literals
• Generic math support
• Generic attributes
• UTF-8 string literals
• Newlines in string interpolation expressions
• List patterns
• File-local types
• Required members
• Auto-default structs
• Pattern matchSpan<char>on a constantstring
• Extendedname of scope
• Numeric IntPtr
• reffields andscoped ref
• Improved method group conversion to delegate
• Warning wave 7