Why do I keep on looping after I've filled in book info and why doesn't it write in to a file? - vb.net

Question

Basically, it's an OOP task which creates a class called book. In the submain, there'll be a menu for the user to add new books/ view all book titles/ view all book authors and exit. I haven't got into the view all book titles and authors yet because at the moment I'm getting looped back again after I inserted the book's details. Which also prevents writing to a text file that will store previous books.
' Description: Making a menu that lets the user store their books info (like a librarian).
Sub Main()
'making a book using the attributes and methods
Dim title As String = ""
Dim datepublished As Date = #01/01/0001# ' date is in month/day/year
Dim pagenum As Integer = 0
Dim isbn As String = ""
Dim author As String = ""
Dim amountbooks As Integer = 0
Dim newbook As Book = New Book()
Dim choice As String = ""
'Writing and Reading a text file.
'CreateText creates a text file and returns system.io.streamwriter object.
Dim streamwriter As System.IO.StreamWriter
streamwriter = System.IO.File.CreateText("C:\Users\Local_PC\Desktop\Try_oop_book\bookrecords.txt")
'Making a menu for the client
' A While loop for the menu that checks the user's input
While choice <> "1" Or choice <> "2" Or choice <> "3" Or choice <> "4"
Console.Clear()
Console.WriteLine("----------LIBRARY MENU----------")
Console.WriteLine("[ 1 ]" & "Add New Book(s)")
Console.WriteLine("[ 2 ]" & "View all Book Titles")
Console.WriteLine("[ 3 ]" & "View all Authors")
Console.WriteLine("[ 4 ]" & "Exit")
choice = Console.ReadLine()
If choice <> "1" And choice <> "2" And choice <> "3" And choice <> "4" Then
Console.WriteLine("Please type in a valid input next time, press enter to retry again.")
Console.ReadLine()
Else
'Using choice, it goes to check which menu the user typed in.
If choice = "1" Then
'The user has chosen 1 which is to add new book(s) to the menu system.
'Setting the title of the book using mybook.setTitle
Console.WriteLine("How many books do you want to add?")
amountbooks = Console.ReadLine()
Dim bookarr(amountbooks) As Book 'This will initialise after amountbooks has been entered. Prevents from getting invalid index number of 0.
For x = 1 To amountbooks ' This loop will go over how many amount of books the user wants to add in to.
bookarr(x) = New Book()
Console.WriteLine("What is the title of the book?")
title = Console.ReadLine() 'This gives the value to store inside the variable 'title'
newbook.setTitle(title) 'This line will set that 'title' into array bookarr
Console.WriteLine("When is the book published?")
datepublished = Console.ReadLine()
newbook.setDatePublished(datepublished)
Console.WriteLine("How many page numbers are there?")
pagenum = Console.ReadLine()
newbook.setPageNum(pagenum)
Console.WriteLine("What is the ISBN(code) of the book?")
isbn = Console.ReadLine()
newbook.setISBN(isbn)
Console.WriteLine("Who is the author of the book?")
author = Console.ReadLine()
newbook.setAuthor(author)
Next x
End If
End If
End While
streamwriter.WriteLine(newbook)
End Sub

Answer 1

Change the while clause to replace 'Or' with 'AndAlso':
While choice <> "1" AndAlso choice <> "2" AndAlso choice <> "3" AndAlso choice <> "4"
In your current code if choice is 3 (for example) then it is not 1, 2 or 4 and the code will enter the while loop - in other words you have an infinite loop.