using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Text.RegularExpressions;

namespace ExistsInString

{

    class Program

    {

        static void Main(string[] args)

        {

            string str0 = "|456|";

            string str1 = "|444|";

            string str2 = "|111|222|333|444|555|666|777|888|999|000|";

            //------------------------------------------

            //String.Contains方法

            if (str2.Contains(str0))

                Console.WriteLine("String.Contains->true");

            else

                Console.WriteLine("String.Contains->false");

            if (str2.Contains(str1))

                Console.WriteLine("String.Contains->true");

            else

                Console.WriteLine("String.Contains->false");

            //------------------------------------------

            //String.IndexOf方法

            int val1 = str2.IndexOf(str0);//不存在返回-1

            Console.WriteLine("String.IndexOf(no exists)->" + val1);

            int val2 = str2.IndexOf(str1);//存在返回str1首字符所在str2中的位置(>=0)

            Console.WriteLine("String.IndexOf(exists)->" + val2);

            //------------------------------------------

            //正则匹配方法

            if (Regex.Match(str2, "[|]456[|]").Success)

                Console.WriteLine("Regex.Match(no exists)->true");

            else

                Console.WriteLine("Regex.Match(no exists)->false");

            if (Regex.Match(str2, "[|]444[|]").Success)

                Console.WriteLine("Regex.Match(exists)->true");

            else

                Console.WriteLine("Regex.Match(exists)->false");

            Console.ReadKey();

            /*

             *如果上述三种方式都处理大量数据，效率如何呢？

             *以下循环六组数据说明

             */

            int loopCount = (int)10e6;

            DateTime lasttime = DateTime.Now;

            DateTime nowtime = DateTime.Now;

            for (int loop = ; loop < ; loop++)

            {

                Console.WriteLine("\r\nloop " + loop + " >>>>>>>");

                //------------------------------------------

                //String.Contains方法

                //no exists

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (str2.Contains(str0)) { };

                nowtime = DateTime.Now;

                TimeSpan tsStrConNoExists = nowtime - lasttime;

                //exists

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (str2.Contains(str1)) { };

                nowtime = DateTime.Now;

                TimeSpan tsStrConExists = nowtime - lasttime;

                //------------------------------------------

                //String.IndexOf方法

                //no exists

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (str2.IndexOf(str0) >= ) { };//上述已经提到不存在返回-1，存在返回一个非负整数，这里为什么不用 == -1 ，而是用了 >= 0 ，这是一个值得深思的问题？

                nowtime = DateTime.Now;

                TimeSpan tsStrIndNoExists = nowtime - lasttime;

                //exists

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (str2.IndexOf(str1) >= ) { };

                nowtime = DateTime.Now;

                TimeSpan tsStrIndExists = nowtime - lasttime;

                //------------------------------------------

                //Regex.Match方法

                //no exists

                Regex Reg0 = new Regex("[|]456[|]");

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (Reg0.Match(str2).Success) { };

                nowtime = DateTime.Now;

                TimeSpan tsStrRegNoExists = nowtime - lasttime;

                //exists

                Regex Reg1 = new Regex("[|]444[|]");

                lasttime = DateTime.Now;

                for (int i = ; i < loopCount; i++)

                    if (Reg1.Match(str2).Success) { };

                nowtime = DateTime.Now;

                TimeSpan tsStrRegExists = nowtime - lasttime;

                Console.WriteLine("no exists >>>");

                Console.WriteLine("tsStrConNoExists = " + tsStrConNoExists.Milliseconds);

                Console.WriteLine("tsStrIndNoExists = " + tsStrIndNoExists.Milliseconds);

                Console.WriteLine("tsStrRegNoExists = " + tsStrRegNoExists.Milliseconds);

                Console.WriteLine("exists >>>");

                Console.WriteLine("tsStrConExists = " + tsStrConExists.Milliseconds);

                Console.WriteLine("tsStrIndExists = " + tsStrIndExists.Milliseconds);

                Console.WriteLine("tsStrRegExists = " + tsStrRegExists.Milliseconds);

            }

            Console.ReadKey();

        }

    }

}