C#——匿名类型

匿名类型：

*提供了一种方便的方法，用来将一组只读属性封装到单个对象中，而无需首先显示定义一个类型

*类型名由编译器生成

*结合new运算符和对象初始值设定项创建匿名类型

*匿名类型是class类型，直接派生自object

*如下示例，查找年龄是两岁的猫

    public class Cat
    {
        // Auto-implemented properties.
        public int Age { get; set; }
        public string Name { get; set; }

        public Cat()
        {
        }

        public Cat(string name)
        {
            this.Name = name;
        }
    }

        static void Main(string[] args)
        {

            List<Cat> cats = new List<Cat>
            {
                new Cat { Name = "Sylvester", Age = 8 },
                new Cat { Name = "Whiskers", Age = 2 },
                new Cat { Name = "Sasha", Age = 14 }
            };

            var cat = from pet in cats
                      where pet.Age == 2
                      select pet;

            Console.WriteLine($"{cat.First().Name}'age is 2 ");

            //output
            //Whiskers'age is 2
        }