Imports System.Text
Public Class Form1
Public quoteStr As String = Global.Microsoft.VisualBasic.ChrW(34)
Public illegalChar As Boolean = False
Public asteriskReplacement As New StringBuilder(" ", 4)
Public asteriskComboIndex As Integer = 0
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim keyboardCharacters As String() = {" single space", "- hyphen", _
" - <single space>hyphen<single space>", "` open single quote",_
"' close single quote", "_ underscore", "=", "~", "!", "@", "#", "$",_
"%", "^", "&", "(", ")", "+", "[", "{", "}", ";", quoteStr, ",", ".", _
"1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "a", "b", "c", "d",_
"e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s",_
"t", "u", "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G",_
"H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T",_
"U", "V", "W", "X", "Y", "Z"} ComboBox1.Items.AddRange(keyboardCharacters)
ComboBox1.SelectedIndex = asteriskComboIndex
End Sub
Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)_
Handles ComboBox1.SelectedIndexChanged
Dim indexS As String = ComboBox1.SelectedIndex
MsgBox("SelectedIndex _" + indexS + "_")
Dim index As Integer = ComboBox1.SelectedIndex
asteriskComboIndex = index
WhichChar(ComboBox1, asteriskReplacement, index)
MsgBox("SelectedIndexChanged SelectedText _" + ComboBox1.SelectedText + "_")
End Sub
Public Sub WhichChar(ByVal CBox As ComboBox, ByRef retVal As StringBuilder, ByVal index As Integer)
MsgBox("WhichChar CBox.SelectedText _" + CBox.SelectedText + "_")
Dim selectedItem As New Object
selectedItem = CBox.SelectedItem
ClearStrBuilder(retVal)
MsgBox("timing")
Select Case index
Case 0 'single space
retVal.Append(" ")
Case 1 'hyphen
retVal.Append("-")
Case 2 'single space>hyphen<single space>
retVal.Append(" - ")
Case 3 'open single quote
retVal.Append("`")
Case 4 ' close single quote
retVal.Append("'")
Case 5 'underscore
retVal.Append("_")
Case Else 'everything else
retVal.Append(CBox.SelectedText)
End Select
End Sub
Private Sub ClearStrBuilder(ByRef str As StringBuilder)
Dim holdStr As String = str.ToString()
str = str.Remove(0, holdStr.Length)
str.Length = 0
End Sub
Private Sub Form1_FormClosed(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosedEventArgs)_
Handles MyBase.FormClosed
MsgBox("Form1_FormClosed asteriskReplacement _" + asteriskReplacement.ToString() + "_")
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox("Button1_Click asteriskReplacement _" + asteriskReplacement.ToString() + "_")
MsgBox("Button1_Click ComboBox1.SelectedText _" + ComboBox1.SelectedText + "_")
End Sub
Private Sub ComboBox1_Leave(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.Leave
Dim indexS As String = ComboBox1.SelectedIndex
MsgBox("ComboBox1 SelectedIndex _" + indexS + "_")
Dim index As Integer = ComboBox1.SelectedIndex
asteriskComboIndex = index
WhichChar(ComboBox1, asteriskReplacement, index)
End Sub
End Class
Create a default Windows Form Project with a default ComboBox and default Button in the default Form. Double-click the Form to open the code window, replace everything there with the above code. Run the code in the debugger – menu item Debug/Start Debugging . Close the spurious MsgBox.
Left click once in the ComboBox, press the <a> key (any valid file name character will do); left click the button. Note the two MsgBox messages report that no item was selected in the ComboBox (button click) and that nothing was entered into the asteriskReplacement StringBuilder (you may uncomment the “Timing” MsgBox in WhichChar() to verify that it is not entered). Note that in each message string I have wrapped the variable with a leading and trailing underscore so that null string variables look like __ <two underscores together> and a string containing a single space looks like _ _ <underscore><space><underscore>.
The problem is that when I enter a value via the keyboard (even adding a carriage return) the ComboBox does not enter the _SelectedIndexChanged() function. It does enter the _Leave() function (when I click the button), but note that by the time _Leave() is entered the .SelectedIndex value is no longer valid.
I have spent many hours trying to figure this out; it is obviously a very basic concept and everyone else uses this gadget with ease. I have no idea where I am going wrong. Any help would be greatly appreciated!
Unsolved 
