类型推断

类型推断使用var关键字,编译器可以根据变量的初始化值"推断"变量的类型.


代码如下:

using System;

namespace test
{
    class Program
    {
        static void Main(string[] args)
        {
            var name = "litianping";
            var age = 30;
            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("isRabbitType is type " + isRabbitType.ToString());
            Console.ReadKey();
        }
    }
}
程序结果为:
name is type System.String
age is type System.Int32
isRabbit is type System.Boolean

注意：变量必须初始化，否则编译器就没有推断的依据。声明了变量后，推断出类型后，变量的类型就不能够改变了。