C#泛型（一）泛型方法

namespace GenericsTest
{
    class Program
    {
        // https://www.cnblogs.com/dotnet261010/p/9034594.html
        static void Main(string[] args)
        {
            int iValue = 123;
            string sValue = "456";
            DateTime dtValue = DateTime.Now;

            Console.WriteLine("----------------------------CommonMethod-------------------------------");
            CommonMethod.showInt(iValue);
            CommonMethod.showString(sValue);
            CommonMethod.showDateTime(dtValue);

            Console.WriteLine("----------------------------Object-------------------------------");
            // Object会出现装箱和拆箱，会损耗程序的性能
            CommonMethod.showObject(iValue);
            CommonMethod.showObject(sValue);
            CommonMethod.showObject(dtValue);

            Console.WriteLine("----------------------------泛型-------------------------------");
            GenericMethod.show<int>(iValue);
            GenericMethod.show<string>(sValue);
            GenericMethod.show<DateTime>(dtValue);

            Console.WriteLine("----------------------------三种方法执行同样的操作，比较用时长短-------------------------------");
            // 从结果中可以看出：泛型方法的性能最高，其次是普通方法，object方法的性能最低。
            MonitorMethod.Show();


            Console.ReadKey();
        }
    }
}
namespace GenericsTest
{
    public class CommonMethod
    {
        /// <summary>
        /// 打印个int值
        /// </summary>
        /// <param name="iParamenter"></param>
        public static void showInt(int iParameter)
        {
            Console.WriteLine("This is {0}, parameter = {1}, type = {2}.",
                typeof(CommonMethod).Name, iParameter.GetType().Name, iParameter);
        }

        /// <summary>
        /// 打印个string值
        /// </summary>
        /// <param name="sParameter"></param>
        public static void showString(string sParameter)
        {
            Console.WriteLine("This is {0}, parameter = {1}, type = {2}.",
               typeof(CommonMethod).Name, sParameter.GetType().Name, sParameter);
        }

        //、打印个DateTime值
        public static void showDateTime(DateTime dtParameter)
        {
            Console.WriteLine("This is {0}, parameter = {1}, type = {2}.",
               typeof(CommonMethod).Name, dtParameter.GetType().Name, dtParameter);
        }


        /// <summary>
        /// 上面的三个例子进行优化
        /// </summary>
        /// <param name="oParameter"></param>
        public static void showObject(object oParameter)
        {
            Console.WriteLine("This is {0}, parameter = {1}, type = {2}.",
               typeof(CommonMethod).Name, oParameter.GetType().Name, oParameter);
        }
    }
}
namespace GenericsTest
{
    class GenericMethod
    {
        public static void show<T>(T tParameter)
        {
            Console.WriteLine("This is {0}, parameter = {1}, type = {2}.",
                typeof(GenericMethod).Name, tParameter.GetType().Name, tParameter.ToString());

        }
    }
}


namespace GenericsTest
{
    class MonitorMethod
    {
        public static void Show()
        {

            int iValue = 12345;
            long commonSecond = 0;
            long objectSecond = 0;
            long genericSecond = 0;

            {
                Stopwatch watch = new Stopwatch();
                watch.Start();
                for (int i = 0; i < 100000000; i++)
                {
                    ShowInt(iValue);
                }
                watch.Stop();
                commonSecond = watch.ElapsedMilliseconds;
            }
            {
                Stopwatch watch = new Stopwatch();
                watch.Start();
                for (int i = 0; i < 100000000; i++)
                {
                    ShowObject(iValue);
                }
                watch.Stop();
                objectSecond = watch.ElapsedMilliseconds;
            }
            {
                Stopwatch watch = new Stopwatch();
                watch.Start();
                for (int i = 0; i < 100000000; i++)
                {
                    Show<int>(iValue);
                }
                watch.Stop();
                genericSecond = watch.ElapsedMilliseconds;
            }
            Console.WriteLine("commonSecond={0},objectSecond={1},genericSecond={2}."
                , commonSecond, objectSecond, genericSecond);

        }

        #region PrivateMethod
        private static void ShowInt(int iParameter)
        {
            //do nothing
        }
        private static void ShowObject(object oParameter)
        {
            //do nothing
        }
        private static void Show<T>(T tParameter)
        {
            //do nothing
        }
        #endregion
    }
}