如何在C#8.0中编写新的Switch Expression？
switch表达式在表达式上下文中提供类似switch的语义
switch是一个选择语句，它基于与match表达式匹配的模式从一个候选列表中选择一个要执行的switch部分。
如果针对三个或更多条件测试单个表达式，则switch语句通常用作if-else构造的替代方法。
示例
编写开关的新方法
var message = c switch{
Fruits.Red => "The Fruits is red",
Fruits.Green => "The Fruits is green",
Fruits.Blue => "The Fruits is blue"
};例子1
class Program{
public enum Fruits { Red, Green, Blue }
public static void Main(){
Fruits c = (Fruits)(new Random()).Next(0, 3);
switch (c){
case Fruits.Red:
Console.WriteLine("The Fruits is red");
break;
case Fruits.Green:
Console.WriteLine("The Fruits is green");
break;
case Fruits.Blue:
Console.WriteLine("The Fruits is blue");
break;
default:
Console.WriteLine("The Fruits is unknown.");
break;
}
var message = c switch{
Fruits.Red => "The Fruits is red",
Fruits.Green => "The Fruits is green",
Fruits.Blue => "The Fruits is blue"
};
System.Console.WriteLine(message);
Console.ReadLine();
}
}输出结果
The Fruits is green The Fruits is green