匿名类型var自动类型推断

using System;

namespace Frank
{
    public class Sample
    {
        public static void Main(string[] args)
        {
            var name = "Bugs Bunny";
            var age = 25;
            var isRabbit = true;
            Type nameType = name.GetType();
            Type ageType = age.GetType();
            Type isRabbitType = isRabbit.GetType();
            Console.WriteLine("name is type " + nameType.ToString());
            Console.WriteLine("age is type " + ageType.ToString());
            Console.WriteLine("isRabbit is type " + isRabbitType.ToString());
        }
    }
}

输出结果：

name is type System.String
age is type System.Int32
isRabbit is type System.Boolean

使用前必须对匿名类型进行初始化

初始化器不能为空。

一旦声明确定类型后就不能再次改变类型。