using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.IO;

namespace 文件转换

{

    class Program

    {

        static void Main(string[] args)

        {

            FileStream fs = new FileStream("d://test.TXT",FileMode.Open);// open file fs

            StreamReader my_streamReader = new StreamReader(fs); //read

            my_streamReader.BaseStream .Seek (0,SeekOrigin.Begin);

            string arry = "";

            string strLine = my_streamReader.ReadLine();

            do

            {

                string[] split = strLine.Split('=');

                string a = split[0];

                if (a.ToLower() == "ip")

                {

                    arry += strLine + "\n";

                }

                strLine = my_streamReader.ReadLine();

            }

            while (strLine != null && strLine != "");

            my_streamReader.Close();

            my_streamReader.Dispose();

            fs.Close();

            fs.Dispose();

            Console.Write(arry);

            Console.ReadLine();

        }

    }

}

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