1. 5/19/2018 1:01 AM
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

2. The Future of C# Mads Torgersen Dustin Campbell
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

3. Stack Overflow - most popular technologies
stackoverflow.com/insights/survey/2017#most-popular-technologies

4. Stack Overflow - most loved technologies
stackoverflow.com/insights/survey/2017#most-loved-dreaded-and-wanted

5. .NET Language Strategy 1,000,000’s 100,000’s 10,000’s C# VB F#
5/19/2018 1:01 AM
.NET Language Strategy C#
1,000,000’s
Millions VB
100,000’s
Hundreds of thousands F#
10,000’s
Tens of thousands
© 2014 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

6. C# 1,000,000’s 100,000’s 10,000’s C# VB F# Millions
5/19/2018 1:01 AM C# C#
1,000,000’s
Millions VB
100,000’s
Hundreds of thousands F#
10,000’s
Tens of thousands
© 2014 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

7. Visual Basic 1,000,000’s 100,000’s 10,000’s C# VB F# Millions
5/19/2018 1:01 AM
Visual Basic C#
1,000,000’s
Millions VB
100,000’s
Hundreds of thousands F#
10,000’s
Tens of thousands
© 2014 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

8. F# 1,000,000’s 100,000’s 10,000’s C# VB F# Millions
5/19/2018 1:01 AM F# C#
1,000,000’s
Millions VB
100,000’s
Hundreds of thousands F#
10,000’s
Tens of thousands
© 2014 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

9. Demos! More demos! C#: The road ahead C# 7.0 C# 7.1 C# 7.2 C# 7.3
It’s there – use it!
C# 7.1
First point release – tiny features
C# 7.2
Safe, efficient low-level code
C# 7.3
Next steps for pattern matching?
C# 8.0
Major features
Demos!
More demos!

10. C# 8.0: Async streams and disposables
IAsyncEnumerable<Person> people = database.GetPeopleAsync();
foreach await (var p in people) { … }
using await (IAsyncDisposable resource = await store.GetRecordAsync(…)) { … }

11. C# 8.0: Extension everything
extension Enrollee extends Person {
// static field
static Dictionary<Person, Professor> enrollees = new Dictionary<Person, Professor>();
// instance method
public void Enroll(Professor supervisor) { enrollees[this] = supervisor; }
// instance property
public Professor Supervisor => enrollees.TryGetValue(this, out var supervisor) ? supervisor : null;
// static property
public static ICollection<Person> Students => enrollees.Keys;
// instance constructor
public Person(string name, Professor supervisor) : this(name) { this.Enroll(supervisor); } }

12. C# 8.0: Records class Person(string First, string Last);
class Person : IEquatable<Person> {
public string First { get; }
public string Last { get; }
public Person(string First, string Last) => (this.First, this.Last) = (First, Last);
public void Deconstruct(out string First, out string Last)
=> (First, Last) = (this.First, this.Last);
public bool Equals(Person other)
=> other != null && First == other.First && Last == other.Last;
public override bool Equals(object obj) => obj is Person other ? Equals(other) : false;
public override int GetHashCode() => GreatHashFunction(First, Last); … }

13. Resources Language strategy C# design Roslyn
blogs.msdn.microsoft.com/dotnet/2017/02/01/the-net-language-strategy/
blogs.msdn.microsoft.com/vbteam/2017/02/01/digging-deeper-into-the-visual-basic-language-strategy/
C# design
github.com/dotnet/csharplang
blogs.msdn.microsoft.com/dotnet/2017/03/09/new-features-in-c-7-0/
Roslyn
github.com/dotnet/roslyn

14. @roslyn @dcampbell @MadsTorgersen
Where to find us
At the “C#, Visual Basic and F#” booth
@roslyn @dcampbell @MadsTorgersen

15. 5/19/2018 1:01 AM
© Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.