Pattern matching
switch (aa)
{
case {val:12}:
Console.WriteLine("hello");
break;
case A aaa when aa.val2==13:
Console.WriteLine(aaa.val);
break;
}Simplifying switch statements with switch expressions
Animal animal = new Animal() { Name = "tiger" };
string message = animal switch
{
Animal fourLeggedCat when fourLeggedCat.Name=="cat"
=> $"small cat",
Animal wildCat when wildCat.Name == "tiger"
=> $"big cat",
};
Console.WriteLine($"switch expression: {message}");
class Animal
{
public string Name { get; set; }
}with array patterns
int[] mm = new[]{1,2,3,4,5,6,7};
string vv=mm switch
{
int[] vvv when mm is [_,2,_,4,..] => "one",
int[] vvv when mm is {Length: 2} => "two"
};
Console.WriteLine(vv);
int[] mm = new[]{1,2,3,4,5,6,7};
string vv=mm switch
{
[_,2,_,4,..] => "one",
{Length: 2} => "two"
};
Console.WriteLine(vv);relational patterns
bool b=v is (> 32) and (< 66);
string WaterState(int tempInFahrenheit) =>
tempInFahrenheit switch
{
(> 32) and (< 212) => "liquid",
< 32 => "solid",
> 212 => "gas",
32 => "solid/liquid transition",
212 => "liquid / gas transition",
};
var m=(12,44);
var l=new{val1=12,val2=44};
bool res=m is {Item1:12,Item2:_};
bool res2=l is {val1:12,val2:_};
Console.WriteLine($" m is {m}, and l is{l}");