Help for c#

using Microsoft.VisualBasic;
using Microsoft.VisualBasic.CompilerServices;
using RedaX.My;
using System;
using System.Data.OleDb;
using System.IO;
using System.Management;
using System.Security.Cryptography;
using System.Text;
using System.Windows.Forms;

namespace RedaX
{
	[StandardModule]
	internal sealed class GenelModul
	{
		public static OleDbCommand Cmd;

		public static System.Data.OleDb.OleDbConnection OleDbConnection;

		public static string RedaXDataPath;

		public static string WindowsTemp1;

		public static string WindowsTemp2;

		public static bool LisansKontrolEdildi;

		public static DateTime RecDate;

		public static bool LisansDurum;

		public static DateTime LSonTar;

		public static string LisansSahibi;

		public static bool LisansBittiMi;

		public static DateTime DateTimeNow;

		static GenelModul()
		{
			GenelModul.RedaXDataPath = string.Concat(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "\\", Application.ProductName);
			GenelModul.WindowsTemp1 = string.Concat(Environment.GetFolderPath(Environment.SpecialFolder.Templates), "\\");
			GenelModul.WindowsTemp2 = string.Concat(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "\\");
		}

		public static string App_Path()
		{
			return AppDomain.CurrentDomain.BaseDirectory;
		}

		public static void DataConnect()
		{
			if (!File.Exists(string.Concat(GenelModul.RedaXDataPath, "\\Data\\\\ozgundata.mdb")))
			{
				MyProject.Forms.frm_splash.Close();
				Interaction.MsgBox("RedaX veritabanı hatası, Lütfen uygulamayı yeniden kurmayı deneyin!", MsgBoxStyle.Critical, "Veritabanı Hatası!");
				ProjectData.EndApp();
			}
			else
			{
				GenelModul.OleDbConnection = new System.Data.OleDb.OleDbConnection()
				{
					ConnectionString = string.Concat("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=", GenelModul.RedaXDataPath, "\\Data\\\\ozgundata.mdb;Persist Security Info=False;Jet OLEDB:Database Password=SGmafZg4vspLr6Ek7y!?;")
				};
				GenelModul.OleDbConnection.Open();
				GenelModul.Cmd = new OleDbCommand()
				{
					Connection = GenelModul.OleDbConnection
				};
			}
		}

		public static string GetFileContents(string FullPath, ref string ErrInfo = "")
		{
			string str = null;
			try
			{
				StreamReader streamReader = new StreamReader(FullPath);
				string end = streamReader.ReadToEnd();
				streamReader.Close();
				str = end;
			}
			catch (Exception exception)
			{
				ProjectData.SetProjectError(exception);
				ErrInfo = exception.Message;
				ProjectData.ClearProjectError();
			}
			return str;
		}

		public static string HDDSerial()
		{
			string str = null;
			ManagementObjectCollection.ManagementObjectEnumerator enumerator = null;
			using (ManagementObjectCollection managementObjectCollections = (new ManagementObjectSearcher("Select * from  Win32_LogicalDisk")).Get())
			{
				enumerator = managementObjectCollections.GetEnumerator();
				if (enumerator.MoveNext())
				{
					ManagementObject current = (ManagementObject)enumerator.Current;
					Conversions.ToString(current["Volumename"]);
					string str1 = Conversions.ToString(current["Volumeserialnumber"]);
					str = string.Format("{0}", str1);
				}
			}
			return str;
		}

		public static object LisansBitti()
		{
			object obj = null;
			GenelModul.SaveTextToFile(GenelModul.MD5("EXP"), string.Concat(GenelModul.WindowsTemp1, "rdxexp.wav"), "");
			GenelModul.SaveTextToFile(GenelModul.MD5("EXP"), string.Concat(GenelModul.WindowsTemp2, "rdxexc.wav"), "");
			MyProject.Forms.Form1.Enabled = false;
			GenelModul.LisansBittiMi = true;
			Interaction.MsgBox("RedaX Deneme Sürümü kullanım süresi sona ermiştir, RedaX'ı tam sürümde kullanmak için lisans anahtarı girmeniz gerekmektedir!", MsgBoxStyle.Critical, "Deneme Süresi Bitti!");
			MyProject.Forms.frm_lisans.Show();
			return obj;
		}

		public static object LisansKontrol()
		{
			object obj = null;
			string str;
			try
			{
				DateTime time = Daytime.GetTime();
				DateTimeOffset now = DateTimeOffset.Now;
				GenelModul.DateTimeNow = Conversions.ToDate(GenelModul.TarihFormatla(time + now.Offset));
			}
			catch (Exception exception)
			{
				ProjectData.SetProjectError(exception);
				MyProject.Forms.frm_splash.Close();
				Interaction.MsgBox("Lisans kontrolü yapılamıyor!, Lütfen internet bağlantınızın olduğundan emin olun!", MsgBoxStyle.Critical, "Lisans kontrolü yapılamadı!");
				ProjectData.EndApp();
				ProjectData.ClearProjectError();
			}
			if (File.Exists(string.Concat(GenelModul.WindowsTemp1, "rdxins.wav")))
			{
				str = "";
				GenelModul.RecDate = Conversions.ToDate(GenelModul.TarihFormatla(Conversions.ToDate(GenelModul.GetFileContents(string.Concat(GenelModul.WindowsTemp1, "rdxins.wav"), ref str))));
				GenelModul.LSonTar = Conversions.ToDate(GenelModul.TarihFormatla(DateAndTime.DateAdd(DateInterval.Day, 15, GenelModul.RecDate)));
			}
			else
			{
				GenelModul.SaveTextToFile(Conversions.ToString(DateTime.Today), string.Concat(GenelModul.WindowsTemp1, "rdxins.wav"), "");
				GenelModul.RecDate = Conversions.ToDate(GenelModul.TarihFormatla(GenelModul.DateTimeNow));
				GenelModul.LSonTar = DateAndTime.DateAdd(DateInterval.Day, 15, GenelModul.DateTimeNow);
			}
			if (File.Exists(string.Concat(GenelModul.WindowsTemp1, "rdxexp.wav")) | File.Exists(string.Concat(GenelModul.WindowsTemp2, "rdxexc.wav")))
			{
				GenelModul.LisansDurum = false;
				GenelModul.LisansBitti();
			}
			else if (!File.Exists(string.Concat(GenelModul.RedaXDataPath, "\\libocat.bls")))
			{
				GenelModul.LisansDurum = false;
				if (File.Exists(string.Concat(GenelModul.WindowsTemp1, "rdxins.wav")) && Operators.CompareString(GenelModul.TarihFormatla(File.GetCreationTime(string.Concat(GenelModul.WindowsTemp1, "rdxins.wav"))), GenelModul.TarihFormatla(GenelModul.RecDate), false) != 0)
				{
					GenelModul.LisansDurum = false;
					GenelModul.LisansBitti();
				}
				else if (DateAndTime.DateDiff(DateInterval.Day, GenelModul.DateTimeNow, GenelModul.LSonTar, FirstDayOfWeek.Sunday, FirstWeekOfYear.Jan1) > (long)0)
				{
					GenelModul.LisansKontrolEdildi = true;
				}
				else
				{
					GenelModul.LisansBitti();
				}
			}
			else
			{
				str = "";
				string fileContents = GenelModul.GetFileContents(string.Concat(GenelModul.RedaXDataPath, "\\libocat.bls"), ref str);
				string[] strArrays = Strings.Split(fileContents, ",", -1, CompareMethod.Binary);
				if (Operators.CompareString(GenelModul.MD5(string.Concat(strArrays[0], GenelModul.TarihFormatla(GenelModul.RecDate), GenelModul.MD5(GenelModul.HDDSerial()))), strArrays[1], false) == 0)
				{
					GenelModul.LisansSahibi = strArrays[0];
					GenelModul.LisansDurum = true;
					GenelModul.LisansKontrolEdildi = true;
				}
				else
				{
					GenelModul.LisansDurum = false;
					GenelModul.LisansBitti();
				}
			}
			return obj;
		}

		public static string MD5(string yazi)
		{
			string str;
			try
			{
				MD5CryptoServiceProvider mD5CryptoServiceProvider = new MD5CryptoServiceProvider();
				byte[] bytes = Encoding.ASCII.GetBytes(yazi);
				byte[] numArray = mD5CryptoServiceProvider.ComputeHash(bytes);
				int num = checked((int)Math.Round((double)(checked(checked((int)numArray.Length) * 2)) + (double)(checked((int)numArray.Length)) / 8));
				StringBuilder stringBuilder = new StringBuilder(num);
				int length = checked(checked((int)numArray.Length) - 1);
				for (int i = 0; i <= length; i++)
				{
					stringBuilder.Append(BitConverter.ToString(numArray, i, 1));
				}
				str = stringBuilder.ToString().TrimEnd(new char[] { ' ' });
			}
			catch (Exception exception)
			{
				ProjectData.SetProjectError(exception);
				str = "0";
				ProjectData.ClearProjectError();
			}
			return str;
		}

		public static bool SaveTextToFile(string strData, string FullPath, string ErrInfo = "")
		{
			bool flag = false;
			try
			{
				StreamWriter streamWriter = new StreamWriter(FullPath);
				streamWriter.Write(strData);
				streamWriter.Close();
				flag = true;
			}
			catch (Exception exception)
			{
				ProjectData.SetProjectError(exception);
				ErrInfo = exception.Message;
				ProjectData.ClearProjectError();
			}
			return flag;
		}

		public static string StringTemizle(string girdi)
		{
			return Strings.Replace(girdi, "'", "", 1, -1, CompareMethod.Binary);
		}

		public static string TarihFormatla(DateTime GirisTarih)
		{
			string str;
			string str1;
			int day;
			if (Strings.Len(GirisTarih.Day.ToString()) != 2)
			{
				day = GirisTarih.Day;
				str1 = string.Concat("0", day.ToString());
			}
			else
			{
				str1 = Conversions.ToString(GirisTarih.Day);
			}
			if (Strings.Len(GirisTarih.Month.ToString()) != 2)
			{
				day = GirisTarih.Month;
				str = string.Concat("0", day.ToString());
			}
			else
			{
				str = Conversions.ToString(GirisTarih.Month);
			}
			string[] strArrays = new string[] { str1, ".", str, ".", null };
			day = GirisTarih.Year;
			strArrays[4] = day.ToString();
			return string.Concat(strArrays);
		}
	}
}