C# Read file text จะค้นหาคำใน Notepad เช่น connect: [xxxx] สามารถทำได้ด้วยวิธีไหนบ้างครับ

TORServices.clsINI.WriteValue(@"C:\txt.txt","path","path_1","TOR@Chemistry 555");
string path = TORServices.clsINI.ReadValue(@"C:\txt.txt","path","path_1");

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;

namespace TORServices
{
    public static class clsINI
    {
        [DllImport("kernel32.dll", EntryPoint = "GetPrivateProfileStringA", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
        private static extern int GetPrivateProfileString(string lpApplicationName, string lpKeyName, string lpDefault, global::System.Text.StringBuilder lpReturnedString, int nSize, string lpFileName);
        [DllImport("kernel32.dll", EntryPoint = "WritePrivateProfileStringA", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
        private static extern int WritePrivateProfileString(string lpApplicationName, string lpKeyName, string lpString, string lpFileName);
        public static string ReadValue(string Path, string section, string key)
        {
            global::System.Text.StringBuilder sb = new global::System.Text.StringBuilder(255);
            dynamic i = GetPrivateProfileString(section, key, "", sb, 255, Path);
            return sb.ToString();
        }
        public static void WriteValue(string Path, string section, string key, string value) { WritePrivateProfileString(section, key, value, Path); }
            public static string textFileReader(string pathFileName)
   {
     string line;
     StreamReader fs;
     try 
     {
        fs = new StreamReader(pathFileName);
        line = fs.ReadToEnd();

        /* อ่าน Encode จาก String ที่อ่านมาได้จาก text file */ 
        Encoding encodeSource = Encoding.GetEncoding(fs.CurrentEncoding.CodePage);
        fs.Close();

        //* ............ */
        Encoding systemEncode = Encoding.Default; 
        Encoding targetEncode = encodeSource;

        /* สั่ง getbyte array จาก string ที่เราอ่านมา */
        byte[] srcData = systemEncode.GetBytes( line );
        byte[] dstData;

        /* ถ้าเป้น Encode ต่างกัน windows และ text file ให้ Convert byte array ไปเป็น text file encode */
        if( targetEncode != systemEncode )
          dstData = Encoding.Convert( systemEncode, targetEncode, srcData );
        else 
          dstData = srcData;

        /* convert bytearray ไปเป็น string ด้วย text file encode */
        return  targetEncode.GetString(dstData);

     }
     catch(Exception ex)
     {
        throw new IOException("cannot find " + pathFileName,ex);
     }

   }
        public static System.Collections.Generic.List<string> textFileReaderFormline(string pathFileName)
        {

            System.Collections.Generic.List<string> list = new System.Collections.Generic.List<string>();
            System.IO.StreamReader fs;
            fs = new System.IO.StreamReader(pathFileName, System.Text.Encoding.GetEncoding(874));

            string line;
            while ((line = fs.ReadLine()) != null)
            {
                list.Add(line);
            }
            return list;

        }
    }
}