Please help me with this prblem;
The Project name of this, is called "PERSONAL ASSISTANT"
It is aim helping users Add,Edit,Search and DELETE RECORDS FROM FILES.
here is what i have tried so far
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
namespace NiitProject
{
   class PersonalAssistant
   {
      public void ShowIntro()
      {
         //Guide to the user
         Console.Write("\nHELLO");
         Console.WriteLine("\n\t\t ************** Your are Welcome!!! *************** ");
         Console.WriteLine("\nTo Your ***PERSONAL ASSISTANT PROGRAM*** ");
         Console.Write("This Program is Aim at helping you store Contact Details and Details of meetings");
         Console.Write("\\Appointments.");
         Console.WriteLine("\n\nKindly Enter Letter \\m\\ to view the Main Menu");
         //To catch a user Defined Exception
         try
         {
            char key = Convert.ToChar(Console.ReadLine());
         }
         catch (FormatException e)
         {
            //Message To be Displayed when tried
            Console.WriteLine(e.Message);
         }
         Console.WriteLine("\n\t\t ***** MAIN MENU *****");
         Console.WriteLine("\n(1.) Contact");
         Console.WriteLine("\n(2.) Meetings\\Appointment");
         Console.WriteLine("\nPress 1 OR 2 to Select any of the above Operations");
         Main_Menu_Condition_For_Contact();
      }
      public void Main_Menu_Condition_For_Contact()//condition for Each Menu
      {
         try
         {
            //variable used for Menu Selection
            int InputNum = Convert.ToInt32(Console.ReadLine());
            //Input Validation Condition
            while ((InputNum < 1) || (InputNum > 2))
            {
               //Input Validation Message
               Console.WriteLine("\nINVALID NUMBER ENTERED.Before You can continue Enter 1 OR 2");
               //Repeat Input Number
               InputNum = Convert.ToInt32(Console.ReadLine());
            }
            //condition for Contact Menu
            if (InputNum == 1)
            {
               //SubMenu List1
               Console.Write("\n\t\t*****SUBMENUS FOR CONTACT*****");
               Console.WriteLine("\n(1.) Add new Contact");
               Console.WriteLine("\n(2.) Delete Contact");
               Console.WriteLine("\n(3.) Edit Contact");
               Console.WriteLine("\n(4.) Search Contact");
               Console.WriteLine("\nPress 1,2,3 OR 4 to Select any of the above Operations");
               //SubMenu Method for contact is been Called
               SubMenuCondition_ForContact();
            }
            else if (InputNum == 2)
            {
               //Submenu List1 for Meeting
               Console.Write("\n\t\t***** SUBMENUS FOR MEETING//APPOINTMENT *****");
               Console.WriteLine("\n(1.) Add an Appointment ");
               Console.WriteLine("\n(2.) Delete an Appointment");
               Console.WriteLine("\n(3.) Edit an Appointment");
               Console.WriteLine("\n(4.) Search for an Appointment");
               //Message to prompt user to enter the correct value
               Console.WriteLine("\nPress 1,2,3 OR 4 to Select any of the above Operations");
               //SubMenu Method for Appointment is been Called
               Sub_Menu_Condition_4_Meeting();
            }
         }
         //User Defined Exception
         catch (FormatException E)
         {
            //To Display Exception Message
            Console.WriteLine(E.Message);
         }
      }
      public void SubMenuCondition_ForContact()//Conditions for SubMenu
      {
         //Variable to Accept A Valid Value
         int InputMenu2 = Convert.ToInt32(Console.ReadLine());
         //Input Validation Condition
         while ((InputMenu2 < 1) || (InputMenu2 > 4))
         {
            Console.WriteLine("\nINVALID NUMBER ENTERED.Before You can continue Enter 1,2,3 OR 4");
            //Variable to accept a Value
            InputMenu2 = Convert.ToInt32(Console.ReadLine());
         }
         //Statement to Carry out operation from any of the contact SubMenu Options
         //int InputSelectionForContact;
         switch (InputMenu2)
         {
            case 1:
               {
                  AddContact();
               }
               break;
            case 2:
               {
                  DELETE();
               }
               break;
            case 3:
               {
                  Edit_Contact();
               }
               break;
            case 4:
               {
                  Search_Contact();
               }
               break;
            default:
               Console.WriteLine("\nNo operation for that value");
               break;
         }
      }
      public void AddContact()
      {
         FileStream fs = new FileStream("PersonalAssistant.txt", FileMode.Append, FileAccess.Write);
         StreamWriter writer = new StreamWriter(fs);
         Console.WriteLine("\nHow many Contacts do want to Add");
         int Add = Convert.ToInt32(Console.ReadLine());
         string NameContact;
         double ContactPhone;
         string Address;
         for (int Index = 0; Index < Add; Index++)
         {
            Console.WriteLine("\nEnter the Name of Contact {0}", Index + 1);
            NameContact = Console.ReadLine();
            Console.WriteLine();
            Console.WriteLine("\nEnter the Phone Number ");
            ContactPhone = Convert.ToDouble(Console.ReadLine());
            Console.WriteLine();
            Console.WriteLine("\nEnter the Contact Address");
            Address = Console.ReadLine();
            //Leave A BlankLine
            Console.WriteLine();
            //Writes Contacts To File
            writer.Write(NameContact);
            //Write PhoneNumber To file
            writer.Write(ContactPhone);
            //Console.WriteLine();
            writer.Write(Address);
            Console.WriteLine();
            Console.WriteLine("\nYour Contact Has been Added");
         }
         writer.Flush();
         writer.Close();
         fs.Close();
      }
      public void DELETE()
      {
         FileStream fs = new FileStream("PersonalAssistant.txt", FileMode.Open, FileAccess.Read, FileShare.Delete);
         //StreamReader sr = new StreamReader(fs);
         StreamReader sr = new StreamReader(fs);
         sr.BaseStream.Seek(0, SeekOrigin.Begin);
         string Receive = sr.ReadLine();
         Boolean found = false;
         Console.WriteLine("\nEnter the Name of contact that which to delete from the file");
         string SearchValue = Console.ReadLine();
         SearchValue = Receive;
         while ((Receive != null) && (found == false))
         {
            if (Receive == SearchValue)
            {
               found = true;
               SearchValue = Receive;
               File.Delete(SearchValue);
            }
            sr.Close();
            fs.Close();
         }
         Console.WriteLine("\nThe Data has been Deleted");
      }
      public void Edit_Contact()
      {
         FileStream fs = new FileStream("PersonalAssistant.txt", FileMode.Append, FileAccess.Write, FileShare.Inheritable);
         //FileStream f=new FileStream("temp.txt");
         StreamWriter sr = new StreamWriter(fs);
         Console.WriteLine("\nHow Many Contact do which to modify");
         int Number = Convert.ToInt32(Console.ReadLine());
         for (int Index = 0; Index < Number; Index++)
         {
            Console.WriteLine("\nEnter the New Name for contact {0}", Index + 1);
            string Name = Console.ReadLine();
            Console.WriteLine("\nEnter the New Phone Number");
            double Phone = Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("\nEnter the New Address for Contact");
            string Address = Console.ReadLine();
            //Display Blank Line
            Console.WriteLine();
            sr.WriteLine(Name);
            sr.WriteLine(Phone);
            sr.WriteLine(Address);
         }
         sr.Flush();
         sr.Close();
         fs.Close();
         Console.WriteLine("\nYou have Successfully Modified Your Record");
      }
      public void Search_Contact()
      {
         FileStream fs = new FileStream("PersonalAssistant.txt", FileMode.Open, FileAccess.Read);
         StreamReader sr = new StreamReader(fs);
         sr.BaseStream.Seek(0, SeekOrigin.Begin);
         string Name, Address;
         double phone;
         Name = sr.ReadLine();
         phone = sr.Read();
         Address = sr.ReadLine();
         Boolean found = false;
         Console.WriteLine("\nEnter The name of the Contact to Search for");
         string SearchName = Console.ReadLine();
         if ((Name == SearchName) || (found = false))
         {
            found = true;
            //SearchName = Name;
            Console.WriteLine("{0}", Name);
            //Name = sr.ReadLine();
            Console.WriteLine("{0}", phone);
            //phone = sr.Read();
            Console.WriteLine("{0}", Address);
            //Address = sr.ReadLine();
         }
         fs.Flush();
         sr.Close();
         fs.Close();
         Console.WriteLine("{0} ", SearchName + "Was not found");
      }
      public void Sub_Menu_Condition_4_Meeting()
      {
         //Variable to Accept A Valid Value
         int InputMenu2 = Convert.ToInt32(Console.ReadLine());
         //Input Validation Condition
         while ((InputMenu2 < 1) || (InputMenu2 > 4))
         {
            Console.WriteLine("\nINVALID NUMBER ENTERED.Before You can continue Enter 1,2,3 OR 4");
            //Variable to accept a Value
            InputMenu2 = Convert.ToInt32(Console.ReadLine());
         }
         //Statement to Carry out operation from any of the SubMenu Options
         //int InputSelectionForContact;
         switch (InputMenu2)
         {
            case 1:
               {
                  Add_Meeting();
               }
               break;
            case 2:
               {
                  DELETE_Meeting();
               }
               break;
            case 3:
               {
                  Edit_Meeting();
               }
               break;
            case 4:
               {
                  Search_Meeting();
               }
               break;
            default:
               Console.WriteLine("\nNo operation for that value");
               break;
         }
      }
      public void Add_Meeting()
      {
         FileStream fs = new FileStream("Meeting.txt", FileMode.Append, FileAccess.Write);
         StreamWriter writer = new StreamWriter(fs);
         Console.WriteLine("\nHow many meeting(s) do want to Add");
         int Add = Convert.ToInt32(Console.ReadLine());
         string Meeting_Subject;
         string Meeting_Address;
         double Meeting_DATE;
         for (int Index = 0; Index < Add; Index++)
         {
            Console.WriteLine("\nEnter the Subject of Meeting {0}", Index + 1);
            Meeting_Subject = Console.ReadLine();
            Console.WriteLine();
            Console.WriteLine("\nEnter the Meeting Address ");
            Meeting_Address = Console.ReadLine();
            Console.WriteLine();
            Console.WriteLine("\nEnter the Date of the Meeting");
            Meeting_DATE = Convert.ToDouble(Console.ReadLine());
            //Leave A BlankLine
            Console.WriteLine();
            //Writes MeetingSubject To File
            writer.Write(Meeting_Subject);
            //Write Meeting Address To file
            writer.Write(Meeting_Address);
            //Write Meeting Date to file
            writer.Write(Meeting_DATE);
            Console.WriteLine();
            Console.WriteLine("\nYour Meeting Has been Added");
         }
         writer.Flush();
         writer.Close();
         fs.Close();
      }
      public void DELETE_Meeting()
      {
         FileStream fs = new FileStream("Meeting.txt", FileMode.Open, FileAccess.Read, FileShare.Delete);
         //StreamReader sr = new StreamReader(fs);
         StreamReader sr = new StreamReader(fs);
         sr.BaseStream.Seek(0, SeekOrigin.Begin);
         string Receive = sr.ReadLine();
         Boolean found = false;
         Console.WriteLine("\nEnter the Subject of the meeting that which to delete from the file");
         string SearchValue = Console.ReadLine();
         SearchValue = Receive;
         while ((Receive != null) && (found == false))
         {
            if (Receive == SearchValue)
            {
               found = true;
               SearchValue = Receive;
               File.Delete(SearchValue);
            }
            sr.Close();
            fs.Close();
         }
         Console.WriteLine("\nThe Meeting has been Deleted");
      }
      public void Edit_Meeting()
      {
         FileStream fs = new FileStream("Meeting.txt", FileMode.Append, FileAccess.Write);
         //FileStream f=new FileStream("temp.txt");
         StreamWriter sr = new StreamWriter(fs);
         Console.WriteLine("\nHow Many Meeting do which to modify");
         int Number = Convert.ToInt32(Console.ReadLine());
         for (int Index = 0; Index < Number; Index++)
         {
            Console.WriteLine("\nEnter the New Subject for Meeting {0}", Index + 1);
            string New_Meeting_Subject = Console.ReadLine();
            Console.WriteLine("\nEnter The New Date For Meeting");
            double New_Meeting_DATE = Convert.ToDouble(Console.ReadLine());
            Console.WriteLine("\nEnter the New Address for Contact");
            double New_Meeting_Address = Convert.ToDouble(Console.ReadLine());
            //Display Blank Line
            Console.WriteLine();
            sr.WriteLine(New_Meeting_Subject);
            sr.WriteLine(New_Meeting_DATE);
            sr.WriteLine(New_Meeting_Address);
         }
         sr.Flush();
         sr.Close();
         fs.Close();
      }
      public void Search_Meeting()
      {
         FileStream fs = new FileStream("Meeting.txt", FileMode.Open, FileAccess.Read);
         StreamReader sr = new StreamReader(fs);
         sr.BaseStream.Seek(0, SeekOrigin.Begin);
         string Meeting_Subject;
         string Meeting_Address;
         double Meeting_DATE;
         Meeting_Subject = sr.ReadLine();
         Meeting_DATE = sr.Read();
         Meeting_Address = sr.ReadLine();
         //Boolean found = false;
         Console.WriteLine("\nEnter the Name of the Meeting to Search for");
         string SearchMeeting = Console.ReadLine();
         while (Meeting_Subject != null)
         {
            if (Meeting_Subject == SearchMeeting)
            {
               //found = true;
               SearchMeeting = Meeting_Subject;
               Console.WriteLine(Meeting_Subject);
               Meeting_Subject = sr.ReadLine();
               Console.WriteLine(Meeting_Address);
               Meeting_Address = sr.ReadLine();
               Console.WriteLine(Meeting_DATE);
               Meeting_DATE = sr.Read();
               fs.Flush();
               sr.Close();
               fs.Close();
            }
            else
            {
               Console.WriteLine("{0} ", SearchMeeting + "Was not found");
            }
         }
      }
      public static void Main(string[] args)
      {
         PersonalAssistant ps = new PersonalAssistant();
         string keepgoing = "yes";
         do
         {
            ps.ShowIntro();
            Console.WriteLine("\nWill You Like To Perform Another Operation.");
            Console.WriteLine("\nEnter yes to go back to the Main Menu or any other key to cancel");
            keepgoing = Console.ReadLine();
         } while (keepgoing.Equals("yes"));
         Console.ReadLine();
      }
   }
}