Backup current text in textbox after x amount of time

**Grue** · 06-10-2009, 04:46 PM

Hello again everyone!

I'm working on a text editor that, at current, can have open several text documents at any given time. The text is displayed in a large RichTextBox and the open documents are displayed on a sidebar on the left side of the window.

Now, I wanted to make it so that if the program should terminate because of abnormal circumstances, that it would be able to restore the work of the user upon reopening. How I have accomplished this is by making the program create a .tmp file which corresponds exactly to the Index Number of the filename it is associated to in a list. The tmp file, when the file opens, is filled with the data from the original file.

When the user switches to another open document, whatever changes were made to the document they were on are saved and the text of the tmp file corresponding to their selection in the listed files takes the old text's place in the text box.

This I've incorporated without a hitch (well, for the most part; some glitches remain). I've also made it successfully restore files from the .tmp files, which it determines if there was a crash by determining if constantly updated RestoreInfo file exists, as well as the .tmp files. If they do, the user has the option to recover their work. When the program closes normally, the tmp files and RestoreInfo file are deleted.

What I would like to implement is a feature that backs up the currently opened text document after, say, 10 minutes and saves it to it's respective tmp file, as some users, whether it be programming or otherwise, take a while to think on what they're doing and unless they switch their document choice around constantly, the backup's do not stay current.

I looked at the Background Worker that VB.NET comes with stock, but I have no idea if that would suit my purposes, or how to use it.

This is the entire code for my text editor. Sorry for the sloppyness:

Code:

'Needed so we can use the constantly utilized StreamReader and StreamWriter functions.
Imports System.IO
Public Class Form1
    'The SyntaxDB File will be used later when the function colorizing feature is implemented.
    Dim SyntaxDBFileAvail As Boolean = True

    'Working directories for temporary application data.
    Dim Dir As String = "C:\Documents and Settings\" + Environ("USERNAME") + "\Application Data\Code!\"
    Dim TempDir As String = "C:\Documents and Settings\" + Environ("USERNAME") + "\Application Data\Code!\temp\"
    Dim DirFile As String = "C:\Documents and Settings\" + Environ("USERNAME") + "\Application Data\Code!\SyntaxDB.txt"

    Dim TempCount As Integer = 0

    'Not sure I need this anymore. I think I adjusted the syntax
    'enough that I can almost remove it without disrupting much.
    Dim SafeIndCount As Integer

    Dim PrevSelInd As Integer = 0
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim SyntaxDBYN As Boolean = My.Computer.FileSystem.FileExists(DirFile)
        Dim TempDirYN As Boolean = My.Computer.FileSystem.DirectoryExists(TempDir)
        Dim TempFYN As Boolean = My.Computer.FileSystem.FileExists(TempDir + "*.tmp")
        Dim FInfoYN As Boolean = My.Computer.FileSystem.FileExists(Dir + "RestoreInfo.info")
        If ListBox1.Items.Count() = 0 Then
        End If

        If FInfoYN = False Then
            File.CreateText(Dir + "RestoreInfo.info")
        ElseIf FInfoYN = True Then
            MessageBox.Show("Code! has detected that it was not closed properly the last time it was exited. Would you like to recover the your project as it was at the time of Code! closed?", "Recover Files?", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1, MessageBoxOptions.DefaultDesktopOnly)
            If MessageBox.Show("Code! has detected that it was not closed properly the last time it was exited. Would you like to recover the your project as it was at the time of Code! closed?", "Recover Files?", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1, MessageBoxOptions.DefaultDesktopOnly) = Windows.Forms.DialogResult.Yes Then
                'Add filenames back to the listbox.
                Dim reader As String
                reader = My.Computer.FileSystem.ReadAllText(Dir + "RestoreInfo.info")
                Dim strs() As String
                strs = Split(reader, Environment.NewLine)
                For Each s As String In strs
                    ListBox1.Items.Add(s)
                Next
                'Change SelectedIndex to first file listing.
                Dim RStreamReader1 As New StreamReader(TempDir + "0.tmp")
                RichTextBox1.Text = RStreamReader1.ReadToEnd.ToString()
                RStreamReader1.Close()
                'FOR FUTURE REFERENCE: TempCount tells how many temporary files there are stored,
                'but it is only cumulative and likely will not be very adaptive to the future change
                'which will allow users to choose files to close out selectively from the listbox.
                TempCount = ListBox1.Items.Count()
                SafeIndCount = TempCount
            ElseIf MessageBox.Show("Code! has detected that it was not closed properly the last time it was exited. Would you like to recover the your project as it was at the time of Code! closed?", "Recover Files?", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1, MessageBoxOptions.DefaultDesktopOnly) = Windows.Forms.DialogResult.No Then
                FInfoYN = False
                'Clean the temp directory so it doesn't cause anomolies, such as old data appearing where it shouldn't.
                If (Directory.Exists(TempDir)) Then
                    For Each fName As String In Directory.GetFiles(TempDir)
                        If File.Exists(fName) Then
                            File.Delete(fName)
                        End If
                    Next
                End If
            End If
        End If
        'Create a fresh SyntaxDB file if there is none.
        If SyntaxDBYN = False Then
            My.Computer.FileSystem.CreateDirectory(Dir)
            SyntaxDBYN = True
            If SyntaxDBYN = True Then
                Try
                    Dim SyntaxDBFile As New StreamWriter(DirFile)
                    SyntaxDBFile.Close()
                    MsgBox("Custom Syntax Database file created. It has been saved in the Application Data directory of your current account. However, if you would like to place it somewhere specific, you may do so by going to Edit>Syntax DB>Advanced and choosing a custom directory.")
                    SyntaxDBFileAvail = True
                    SyntaxDBFile.Close()
                Catch ex As Exception
                    'Perhaps later we can detect whether or not user is running Vista and change
                    'the directory for the database and other app temp data to a user privlidge
                    'accessible folder.
                    MsgBox("Custom Syntax Database file creation failed! The program will continue without it, and it will store custom additions temporarily in memory which will be lost after program is closed. However, you may create one manually in a directory of your choosing and direct the program to it by going to Edit>Syntax DB>Advanced and choosing a custom directory.")
                    SyntaxDBFileAvail = False
                End Try
            ElseIf SyntaxDBYN = True Then
            End If
        End If

        Try
            My.Computer.FileSystem.CreateDirectory(TempDir)
        Catch ex As Exception
            MsgBox("Could not create temporary file directory! Please determine that you have the privlidges to access the Application Data section of your user account and try again. For Vista users, you may wish to use the Administrator Mode with this program.")
        End Try
        MsgBox("Welcome to the Pre-Alpha version of Code! The program current implements a small number of the features it will have later on, such as build intiation functionality for a variety of compilers, syntax suggestion, and formatting aid. More mature Pre-release versions will be open source. Enjoy what you can for now! ;)")
        RichTextBox1.Enabled = False
    End Sub

    'If the user selects to open a single file, it is read to a string in Unicode format, it's name
    'is added to the file list of open text docs, a temporary file created when the selected index
    'changes, and the RestoreInfo file is appended to.
    Private Sub SingleFileToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SingleFileToolStripMenuItem.Click
        OpenFileDialog1.ShowDialog()

        Dim OpenedFileReader As New StreamReader(OpenFileDialog1.FileName.ToString())
        Dim MoveString As String = OpenedFileReader.ReadToEnd()
        RichTextBox1.Text = MoveString.ToString()
        OpenedFileReader.Close()

        ListBox1.Items.Add(Path.GetFileName(OpenFileDialog1.FileName.ToString()))
        ListBox1.SelectedIndex = ListBox1.Items.Count() - 1

        Dim ItemArray(Me.ListBox1.Items.Count - 1) As Object
        Me.ListBox1.Items.CopyTo(ItemArray, 0)
        Dim Data As String = Join(ItemArray, Environment.NewLine)
        'Refresh names list for restore info file.
        File.WriteAllText(Dir + "RestoreInfo.info", Data)

        TempCount = TempCount + 1
        SafeIndCount = TempCount
        If TempCount = 1 Then
            PrevSelInd = 1
        End If
        RichTextBox1.Enabled = True
    End Sub

    'When the index changes, the text document currently in view is backed up to it's respective
    'temporary file so it is safe and may be reopened later, and the temporary file of the newly
    'chosen document is read and it's contents sent to the Rich Text Box.
    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        Dim i As Integer = ListBox1.SelectedIndex()

        Dim BackupStreamWriter As New StreamWriter(TempDir.ToString() + PrevSelInd.ToString() + ".tmp")
        BackupStreamWriter.Write(RichTextBox1.Text.ToString())
        BackupStreamWriter.Close()

        Dim BackupStreamReader As New StreamReader(TempDir.ToString() + i.ToString() + ".tmp")
        RichTextBox1.Text = BackupStreamReader.ReadToEnd.ToString()
        BackupStreamReader.Close()
        PrevSelInd = i
    End Sub

    'Clean the temporary files and restore information if the Form is properly closed.
    Private Sub Form1_FormClosed(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles MyBase.FormClosed
        If (Directory.Exists(TempDir)) Then
            For Each fName As String In Directory.GetFiles(TempDir)
                If File.Exists(fName) Then
                    File.Delete(fName)
                End If
            Next
        End If
        File.Delete(Dir + "RestoreInfo.info")
    End Sub

    'Opens a Save File Dialog, and saves the document as shown in the Rich Text Box according to
    'parameters specified by the user in the SaveFileDialog.
    Private Sub CurrentFileToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CurrentFileToolStripMenuItem.Click
        SaveFileDialog1.ShowDialog()
        File.WriteAllText(SaveFileDialog1.FileName(), RichTextBox1.ToString())
    End Sub

    'Loops through and saves all open text documents to a directory specified by the user.
    Private Sub WholeProjectToolStripMenuItem1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles WholeProjectToolStripMenuItem1.Click
        FolderBrowserDialog1.ShowDialog()

        Dim i As Integer = 0
        Do Until i = ListBox1.Items.Count()
            MsgBox(FolderBrowserDialog1.SelectedPath.ToString() + "\")
            Dim SaveFileWriter As New StreamWriter(FolderBrowserDialog1.SelectedPath.ToString() + "\" + ListBox1.Items.Item(i).ToString())
            SaveFileWriter.Write(File.ReadAllText(TempDir.ToString() + i.ToString() + ".tmp"))
            SaveFileWriter.Close()
            i = i + 1
        Loop
    End Sub

    'Exit program. The Form Closed property still applies here, so this is considered a valid escape.
    Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click
        Application.Exit()
    End Sub

    'This needs a cleanup, but it basically, using the Add button, lets the user create a blank
    'text document to work with.
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If ListBox1.Items.Count >= 1 Then
            ListBox1.Items.Add(TextBox1.Text.ToString())
            RichTextBox1.Text = ""

            Dim NewTextFileWriter As New StreamWriter(TempDir + TempCount.ToString() + ".tmp")
            NewTextFileWriter.Close()
            TempCount = TempCount + 1
            SafeIndCount = TempCount
            PrevSelInd = TempCount
        ElseIf ListBox1.Items.Count = 0 Then
            ListBox1.Items.Add(TextBox1.Text.ToString())
            RichTextBox1.Text = ""

            Dim NewTextFileWriter As New StreamWriter(TempDir + TempCount.ToString() + ".tmp")
            NewTextFileWriter.Close()
            ListBox1.SelectedIndex = TempCount
            SafeIndCount = TempCount
            PrevSelInd = TempCount
            TempCount = TempCount + 1
            SafeIndCount = TempCount
        End If
        RichTextBox1.Enabled = True
    End Sub
End Class

Any ideas or suggestions would be greatly appreciated. :)

EDIT: There's a mistake in something I did with this version of the code that causes an exception trying to load more than 2 files at once. Disregard it if you see it.

EDIT2: I seemed to have screwed up more than that with this code version, but I hope it still gives a clear idea.

**Vswe** · 06-10-2009, 11:12 PM

The thing you need, is that a way to check if 10 minutes have passed?

**Grue** · 06-11-2009, 07:54 AM

Umm...yes, and after ten minutes passes I need it to perform a backup of the text the user is working on, then wait for another ten minutes to pass.

I could use My.Computer.Clock.LocalTime.Minute() to get data to determine if 10 minutes passed (well, until it reaches 59 anyway), but I don't know how I could do that without disrupting the program.

That, I don't know how to accomplish.