所以基本上我正在制作一本跟踪新书，查看标题和作者的图书馆书籍记录。现在，我正处于按字母顺序查看所有标题和作者的阶段，我制作了它们存储在文本文件中。我的老师建议我使用冒泡排序按字母排序，但现在我需要更深入的解释。请帮助一个人谢谢：D
哦，文本文件是这样的（除了最后一个使用＆amp; vbcrlf之外没有空格）：
标题
作者
发布日期
页次
ISBN
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 choice As String = ""
'Declaring an object variable 'filename' which shows the file name (bookrecords.txt) and the path given
Dim filename As String = "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" AndAlso choice <> "2" AndAlso choice <> "3" AndAlso 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")
Console.WriteLine(" ")
Console.Write("Pick a Menu Number: ")
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'
bookarr(x).setTitle(title) 'This line will set that 'title' into array bookarr
Console.WriteLine("Who is the author of the book?")
author = Console.ReadLine()
bookarr(x).setAuthor(author)
Console.WriteLine("When is the book published?")
datepublished = Console.ReadLine()
bookarr(x).setDatePublished(datepublished)
Console.WriteLine("How many page numbers are there?")
pagenum = Console.ReadLine()
bookarr(x).setPageNum(pagenum)
Console.WriteLine("What is the ISBN(code) of the book?")
isbn = Console.ReadLine()
bookarr(x).setISBN(isbn)
Console.Clear() 'clears everything after it has been written into a file
If System.IO.File.Exists(filename) = True Then
' Setting up an object variable for the streamwriter (which is the path folder and its name).
Dim objwriter As New System.IO.StreamWriter(filename, True) ' Has been set to true because the file exists and this will append(ADD) for the next str.
' if a file doesn't exists, it should be false which will ensure that a text file is created first.
objwriter.WriteLine(bookarr(x).getTitle & vbCrLf & bookarr(x).getAuthor & vbCrLf & bookarr(x).getDatePublished & vbCrLf & bookarr(x).getPageNum & vbCrLf & bookarr(x).getISBN & vbCrLf)
objwriter.Close() ' Closes the pathway to filename.
MsgBox("TEXT HAS BEEN SUCCESSFULLY REGISTERED")
Else
MsgBox("FILE DOES NOT EXIST")
End If
Next x
Else
If choice = "2" Then 'View all book titles
Dim readall As String = ""
Dim readtitle As String = ""
If System.IO.File.Exists(filename) = True Then
Dim objreader As New System.IO.StreamReader(filename)
readtitle = objreader.ReadLine
objreader.Close() 'Closes the pathway to filename
Console.WriteLine(readtitle) 'Outputs the all book title in alphabetical
Else
MsgBox("FILE DOES NOT EXIST")
End If
Console.ReadLine()
Else
If choice = "3" Then
Dim readauthor As String
Dim amountauthor As Integer = 0
Dim objreader As New System.IO.StreamReader(filename)
Else
Environment.Exit(0) 'idk I found this online :P but it works for exiting the console
End If
Console.ReadLine()
End If
End If
End If
End While
End Sub