Listbox Multiple KeyPress - vb.net

Question

How can I achieve the search functionality that works with multiple keys in CheckedListBox and ListBox?
Example: I have the following items in the list:
1000
1500
1520
2010
5001
5102
When I press the key 1, instantly search the first hit that match with the first char that starts with '1'.
But, If I want locate the item "5102", the list only will can search the 5, and then, I need go manually to identify the wanted item.

Answer 1

Answering to my own question. This it's a clean solution that doesn't need too much work (All the code can handle in the KeyDown event):
Sub DropDownListBox_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
If Char.IsLetterOrDigit(Chr(e.KeyValue)) Then
e.SuppressKeyPress = True
If TryCast(sender.tag, Timer) Is Nothing Then
Dim vTimer As New Timer
vTimer.Interval = 1000
vTimer.Tag = ""
sender.Tag = vTimer
AddHandler vTimer.Tick,
Sub(Timer As Object, eventsArgs As System.EventArgs)
Timer.Tag = ""
If Not TryCast(sender, CheckedListBox).Visible Then
Timer.dispose() : Timer = Nothing
End If
End Sub
Else
sender.Tag.Stop() : sender.Tag.Start()
sender.Tag.Tag &= Chr(e.KeyValue)
Dim vIndex As Integer = TryCast(sender, CheckedListBox).FindString(sender.Tag.Tag)
If vIndex <> -1 Then TryCast(sender, CheckedListBox).SelectedItem = TryCast(sender, CheckedListBox).Items(vIndex)
End If
End If
End Sub
Basically I use the TAG object to keep a Timer running every 1 sec; then, if the user typing several chars, the process will find exactly the wanted text.
Any comment or feedback will be welcome.

Answer 2

Public Class Form1
Dim Type As String
Private Sub ListBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles ListBox1.KeyPress
If Asc(e.KeyChar) <> 8 Then
If Asc(e.KeyChar) < 65 Or Asc(e.KeyChar) > 122 Then
e.Handled = True
' Clear String at Escape key press & Reset Listbox location
If Asc(e.KeyChar) = 27 Then
Type = ""
ListBox1.SelectedIndex = -1
ListBox1.SelectedItem = ListBox1.SelectedIndex
End If
End If
If Asc(e.KeyChar) = 27 Then
' Do not add escape key char to string at key press
Else
' add char one by one after key press
Type &= e.KeyChar
Dim TL As Integer = Type.Length
Dim i As Integer = 0
For i = 0 To ListBox1.Items.Count - 1
' match key press in total items in listbox
'MsgBox(Format$(Mid$(ListBox1.Items(i), 1, TL)))
If Format$(Mid$(ListBox1.Items(i), 1, TL)) = Type Then
ListBox1.SelectedIndex = i
End If
Next
End If
End If
End Sub
End Class