order by date in txt file using vb.net - vb.net

Question

i made a program that takes release date and title from IMDB api and saves them in them in .txt file...can i order them by date somehow
Imports System.IO
Imports System.Xml.Linq
Imports System.Text.RegularExpressions
Public Class Form1
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim _reg As Regex = New Regex("http://www.imdb.com/title/([A-Za-z0-9\-]+)/*?", _
RegexOptions.IgnoreCase)
Dim value As String = TextBox1.Text
Dim m As Match = _reg.Match(value)
If (m.Success) Then
Dim key As String = m.Groups(1).Value
Dim url As String = "http://mymovieapi.com/?id=" + key + "&type=xml&plot=none&episode=0&lang=en-US&aka=simple&release=simple&business=0&tech=0"
Dim Document As XDocument = XDocument.Load(url)
Dim title = Document.Root.Element("title").Value()
Dim releaseDate = Date.ParseExact(Document.Root.Element("release_date").Value,
"yyyyMMdd", System.Globalization.CultureInfo.InstalledUICulture)
TextBox2.Text = "Release Date: " & releaseDate & " / Title: " & title
Else : TextBox2.Text = "Please use IMDB links"
End If
Button2.Enabled = True
End Sub
Private Sub Button2_Click_1(sender As System.Object, e As System.EventArgs) Handles Button2.Click
Dim Writer As System.IO.StreamWriter
Writer = New System.IO.StreamWriter("C:\Users\Azer\Documents\Movies.txt", True)
Writer.Write(TextBox2.Text & vbCrLf)
Writer.Close()
Button2.Enabled = False
End Sub
Private Sub Button4_Click(sender As System.Object, e As System.EventArgs) Handles Button4.Click
Dim Reader As System.IO.StreamReader
Reader = New System.IO.StreamReader("C:\Users\Azer\Documents\Movies.txt")
Dim tempstring As String
Do
tempstring = Reader.ReadLine()
TextBox3.Text = TextBox3.Text + tempstring + vbCrLf
Loop Until tempstring = ""
Reader.Close()
End Sub
Private Sub Button3_Click(sender As System.Object, e As System.EventArgs) Handles Button3.Click
Me.Close()
End Sub
Private Sub Button5_Click(sender As System.Object, e As System.EventArgs) Handles Button5.Click
TextBox3.Clear()
End Sub
End Class

Answer 1

As David said, a database would make this a lot easier. However, if you can't use a database (or have some other reason for doing it this way), here's one way to approach it.
Make a small class that holds the information (to make it easier to sort, like this:
Public Class MovieInfo
Public Property As DateTime
Public Title As String
End Class
Next, read the current file (if it exists) and populate a List<MovieInfo> with the data in it.
Dim movies As String() = File.ReadAllLines("C:\Users\Azer\Documents\Movies.txt")
Dim movieParts = From m in movies
Select m.Split(New String() { "/", ":" }, StringSplitOptions.RemoveEmptyEntries)
Dim parsedDate As DateTime
Dim movieData As List(Of MovieInfo) = (From mi In movieParts
Select New MovieInfo With
{
.ReleaseDate = _
If(DateTime.TryParseExact(mi(1).Trim, "dd.MM.yyyy", _
System.Globalization.CultureInfo.InvariantCulture, _
System.Globalization.DateTimStyle.None, _
parsedDate), parsedDate, DateTime.MinValue),
.Title = mi(3).Trim()
}.ToList()
Essentially the code above reads the text file into an array (one line per element), and then using LINQ splits each line into 4 parts based on : and /. Then it takes the result of that query and builds a List of MovieInfo, with the date string converted to DateTime for easy sorting.
The DateTime.TryParseExact takes an input string of the specified format (in this case, dd.MM.yyyy) and if possible converts it to a DateTime object. If it's successful, it returns true and the DateTime value is in the parsedDate variable. If it's not true, I use the MinValue for DateTime for the ReleaseDate property of the MovieInfo class.
After that, you'll get the new data from your API call and add it to the List of MovieInfo (you'll probably want to eliminate any duplicates). Since you didn't post the format of the data from the API, it's rather hard for me to give you a code sample to parse it, but in a nutshell you can build a second list of MovieInfo objects and then merge the existing and new list together.
Then you sort the List of MovieInfo and overwrite the original text file. Something like this should do the trick:
movieData.Sort(Function(x, y) y.ReleaseDate.CompareTo(x.ReleaseDate))
Dim output As New StringBuilder()
For Each info As MovieInfo in movieData
output.Append("Release Date: ")
output.Append(info.ReleaseDate.ToString("dd.MM.yyyy"))
output.Append(" / Title: ")
output.Append(info.Title)
output.Append(Enviroment.NewLine)
Next
File.WriteAllText("C:\Users\Azer\Documents\Movies.txt", output.ToString())
This code sorts the list with a lambda expression to put the movies in date order (newest to oldest). It then uses a StringBuilder with a For Each loop to build the output, and then writes it to the file (overwriting the file if it already exists).
Note that if you reverse the x and the y in the Sort, you'll get oldest to newest by date.

Answer 2

Dim allLines As String() = File.ReadAllLines("your file name")
System.Array.Sort(allLines)
IO.File.WriteAllLines("your file name", allLines) 'assuming you want to write the file