How to populate ListBox from Dictionary Values? - vb.net

Question

Net
I am attempting to create a function that will allow a user to input text into a RTB and if that text exists in a Dictionary as a Key then a listbox is populated by all the values of the dictionary whose key they are related to , each value populates the listbox in a new line.
the 1st line is highlighted and the user can press the enter button and replace the text in the RTB with the highlighted text .
I'm new to VB so I do not know much .
this is what I have so far.
Public Class Oxnay
Private Sub Oxnay_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Tsort()
End Sub
Private TDictionary As Dictionary(Of String, String())
Public Sub Tsort()
TDictionary = New Dictionary(Of String, String())
TDictionary.Add("ape", {"pl", "tz", "xu"})
TDictionary.Add("lor", {"tv", "px"})
End Sub
Private Sub RichtextBox1_TextChanged(sender As Object, e As EventArgs) Handles RichTextBox1.TextChanged
Dim lastword As String = RichTextBox1.Text.Split(" ").Last
If RichTextBox1.ContainsKey(lastword) Then
'display each string of the dictionary array related to lastword in different lines
'highlight first line
'Some[Code]
Else
ListBox1.Text = ""
End If
End Sub
End Class

Answer 1

For the first "lookup" part, try something like:
Private Sub RichtextBox1_TextChanged(sender As Object, e As EventArgs) Handles RichTextBox1.TextChanged
Dim lastword As String = RichTextBox1.Text.Trim.Split(" ").Last
ListBox1.Items.Clear()
If Not IsNothing(TDictionary) AndAlso TDictionary.ContainsKey(lastword) Then
ListBox1.Items.AddRange(TDictionary(lastword))
End If
End Sub
Then to replace the currently selected text with the selection from the ListBox:
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
If ListBox1.SelectedIndex <> -1 Then
If RichTextBox1.SelectedText <> "" Then
RichTextBox1.SelectedText = ListBox1.SelectedItem.ToString
End If
End If
End Sub