1. C# Language & .NET Platform 3rd Lecture
Pavel Ježek
Some of the slides are based on University of Linz .NET presentations.
© University of Linz, Institute for System Software, 2004
published under the Microsoft Curriculum License (

2. C# vs .NET vs CLR C# .NET CLR CLR change 1.0 1.1 2.0 generics
3.0 (WPF, …)
3.0
3.5 (LINQ, …)
(dynamic) 4.0
4.0 (Tasks)
4.0( )
(async/await) 5.0
4.5
4.0( )
better GC
6.0
4.6
4.0( ?)
RyuJIT
7.0
4.7
4.0
.NET Core
Runtime change
2.1
Span<T> support

3. Putting C# into Perspective
Java
Powerful (e.g. multiple inheritance)
Productive (e.g. lot of syntactic sugar)
Simple
Fast
Safe + Less errors in team development, etc. (many features different from Java)
Safe
Not slow
Interoperable
(Source portable)
(Binary portable)
Binary portable

4. Implicitly Typed Local Variables
Examples:
var i = 5; var s = "Hello"; var d = 1.0; var numbers = new int[] {1, 2, 3}; var orders = new Dictionary<int,Order>();
Are equivalent to:
int i = 5; string s = "Hello"; double d = 1.0; int[] numbers = new int[] {1, 2, 3}; Dictionary<int,Order> orders = new Dictionary<int,Order>();
Errors:
var x; // Error, no initializer to infer type from var y = {1, 2, 3}; // Error, collection initializer not permitted var z = null; // Error, null type not permitted