几种验证字符串是否全为数字方法的比较

using System;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.Text.RegularExpressions;

namespace IsNumberTest
{
    /// <summary>
    /// 几种验证字符串是否全为数字方法的比较
    /// </summary>
    class Program
    {
        static void Main(string[] args)
        {
            Stopwatch sw;  //测试运行时间
            int times = 50000;  //循环次数
            string testStr = "12a";  //测试用字符串

            #region Regular Expression Method
            sw = Stopwatch.StartNew();
            Regex regIsNum = new Regex (@"^/d+$");
            for (int i = 0; i < times; i++)
            {
                regIsNum.IsMatch(testStr);
            }
            sw.Stop();
            Console.WriteLine("Regular Expression Method Last Time: " + sw.Elapsed.Milliseconds + " ms");
            #endregion

            #region VB.NET IsNumeric Method
            sw = Stopwatch.StartNew();
            for (int i = 0; i < times; i++)
            {
                Microsoft.VisualBasic.Information.IsNumeric(testStr);
            }
            sw.Stop();
            Console.WriteLine("VB.NET IsNumeric Method Last Time: " + sw.Elapsed.Milliseconds + " ms");
            #endregion

            #region Customer Method
            sw = Stopwatch.StartNew();
            for (int i = 0; i < times; i++)
            {
                IsNum(testStr);
            }
            sw.Stop();
            Console.WriteLine("Customer Method Last Time: " + sw.Elapsed.Milliseconds + " ms");
            #endregion

            #region Improved Customer Method
            sw = Stopwatch.StartNew();
            for (int i = 0; i < times; i++)
            {
                ImpIsNum(testStr);
            }
            sw.Stop();
            Console.WriteLine("Improved Customer Method Last Time: " + sw.Elapsed.Milliseconds + " ms");
            #endregion

            #region Catch Exception Method
            sw = Stopwatch.StartNew();
            for (int i = 0; i < times; i++)
            {
                try
                {
                    int.Parse(testStr);
                }
                catch
                {
                    //非数字
                }
            }
            sw.Stop();
            Console.WriteLine("Catch Exception Method Last Time: " + sw.Elapsed.Milliseconds + " ms");
            #endregion

            Console.ReadLine();

        }

        public static bool IsNum(String srcStr)
        {
            for (int i = 0; i < srcStr.Length; i++)
            {
                if (!Char.IsNumber(srcStr, i))
                    return false;
            }
            return true;
        }

        public static bool ImpIsNum(String srcStr)
        {
            for (int i = 0; i < srcStr.Length; i++)
            {
                if (srcStr[i] <= '0' || srcStr[i] >= '9')
                    return false;
            }
            return true;
        }

    }
}