Cannot use the backspace in the AutoCompletion-VB.NET

[KelvinNyota]

I have this problem with my Autocompletion program in VB.NET where you cannot delete text after Autocompletion because once you do that, you cannot be able to Autocomplete again:

The cursor gets very sticky when you press the backspace to correct an error.

Sometimes the words are hidden and you cannot see what you're typing after deleting text.


Here is what needs to be done:


For instance: the text is entered into a TextBox (not the RichTextBox), because it is the one with the AutoComplete functionality, and that text is only put into the RichTextBox when you enter a space (after checking if it needs to be replaced).

If you BackSpace to the start of the textbox and press BackSpace again then you need to hide the TextBox and select the appropriate point in the RichTextBox to edit.

You then need to define a way for the user to seamlessly re-enter the mode where entry is in to the TextBox and AutoComplete and Replacement are active again.

Get my dictionary link from here:

https://onedrive.live.com/redir?resid=B4531AB281EA0794!151&authkey=!AHwEw7adgHmksa4&ithint=file%2ctxt

Here is my code:

Imports System.IO

Public Class Form1

    'This is where you rename a RichTextBox and give it a location'
    Private rtb As New RichTextBox With {.Location = New Point(20, 20), .Dock = DockStyle.Fill}


    'Here you create a textbox and rename is as tb'
    Private WithEvents tb As New TextBox With {.BorderStyle = BorderStyle.None}


    'This the AutoCompleteList is the new list for  the function AutoCompleteStringCollection'
    Private AutoCompleteList As New AutoCompleteStringCollection



    'This one here is for the Replacement List'
    Private ReplacementList As New Dictionary(Of String, String)


    Private SelStart As Integer
    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        'This is where you declare the width of the form and location'

        Width = 900
        CenterToScreen()

        'Here is adding the TextBox into the RichTextBox which is Called tb'
        Controls.AddRange(New Control() {rtb, tb})

        'This I think is where to start counting in order to tell the textbox that, that is a line'
        For count As Integer = 1 To 10000
            AutoCompleteList.Add("Line " & count.ToString)
        Next



        Dim inputFile As String = "C:\Users\Acer\Desktop\out.txt"

        If File.Exists(inputFile) Then


            Using sr As New StreamReader(inputFile)
                While Not sr.EndOfStream
                    Dim wordParts = sr.ReadLine()
                    If wordParts.Count >= 1 Then

                        AutoCompleteList.Add(wordParts.ToString)
                    End If
                End While
            End Using

        End If



        tb.AutoCompleteCustomSource = AutoCompleteList
        tb.AutoCompleteMode = AutoCompleteMode.Suggest
        tb.AutoCompleteSource = AutoCompleteSource.CustomSource
        rtb.Controls.Add(tb)
        tb.Location = New Point(0, 0)
        tb.Select()
    End Sub
    Private Sub tb_TextChanged(sender As Object, e As System.EventArgs) Handles tb.TextChanged
        Dim Txt As String
        If Not String.IsNullOrEmpty(tb.Text) Then
            If tb.Text.EndsWith(" ") Then
                If ReplacementList.ContainsKey(tb.Text.TrimEnd) Then
                    Txt = ReplacementList(tb.Text.TrimEnd)
                Else
                    Txt = tb.Text
                End If
                rtb.SelectedText = Txt & " "
                SelStart = rtb.TextLength
                tb.Location = rtb.GetPositionFromCharIndex(rtb.TextLength)
                tb.Text = ""
            End If
        End If
    End Sub
End Class