Error adding control from toolbox to windows form - vb.net

Question

i have class inherited from textbox , and when i try to add the control from the toolbox i have this error in the picture.
this is class inherited from textbox control ,using listbox control to choose from auto complete list
Public Structure Account
Dim Name As String
Dim Number As String
Public Sub New(Namee As String, Num As String)
Name = Namee
Number = Num
End Sub
Public Overrides Function ToString() As String
Return Name
End Function
End Structure
Public Class AutoCompleteTextBox
Inherits TextBox
Private ACL As List(Of Account), CACL As List(Of Account)
Private CaseSensitive As Boolean
Private MinChar As Integer
Private LS As ListBox
Private OLDText As String
Private PN As Panel
Public Sub New()
MyBase.New
MinTypedCharacters = 2
CaseSesitivity = False
ACL = New List(Of Account)
LS = New ListBox
LS.Name = "SeggestionListBox"
LS.Font = Font
LS.Visible = True
PN = New Panel
PN.Visible = False
PN.Font = Font
PN.AutoSizeMode = AutoSizeMode.GrowAndShrink
PN.ClientSize = New Size(1, 1)
PN.Name = "SeggestionPanel"
PN.Padding = New Padding(0, 0, 0, 0)
PN.Margin = New Padding(0, 0, 0, 0)
PN.BackColor = Color.Transparent
PN.ForeColor = Color.Transparent
PN.PerformLayout()
If Not PN.Controls.Contains(LS) Then
PN.Controls.Add(LS)
End If
LS.Dock = DockStyle.Fill
LS.SelectionMode = SelectionMode.One
AddHandler LS.KeyDown, AddressOf LS_KeyDown
AddHandler LS.MouseClick, AddressOf LS_MouseClick
AddHandler LS.MouseDoubleClick, AddressOf LS_MouseDoubleClick
CACL = New List(Of Account)
LS.DataSource = CACL
OLDText = Text
End Sub
#Region "Properties"
Public Property AutoCompleteList As List(Of Account)
Get
Return ACL
End Get
Set(value As List(Of Account))
ACL.Clear()
ACL = value
End Set
End Property
Public Property CaseSesitivity As Boolean
Get
Return CaseSensitive
End Get
Set(value As Boolean)
CaseSensitive = value
End Set
End Property
Public Property MinTypedCharacters As Integer
Get
Return MinChar
End Get
Set(value As Integer)
MinChar = value
End Set
End Property
Public Property SelectedIndex As Integer
Get
Return LS.SelectedIndex
End Get
Set(value As Integer)
If LS.Items.Count <> 0 Then
LS.SelectedIndex = value
End If
End Set
End Property
Private ReadOnly Property ParentForm As Form
Get
Return Me.Parent.FindForm
End Get
End Property
#End Region
Public Sub HideSuggestionListBox()
If Not ParentForm Is Nothing Then
PN.Hide()
If ParentForm.Controls.Contains(PN) Then
ParentForm.Controls.Remove(PN)
End If
End If
End Sub
Private Function SelectItem() As Boolean
If LS.Items.Count > 0 AndAlso LS.SelectedIndex > -1 Then
Text = LS.SelectedItem.ToString
HideSuggestionListBox()
End If
Return True
End Function
Protected Overrides Sub OnKeyDown(e As KeyEventArgs)
If e.KeyCode = Keys.Up Then
MoveSelection(SelectedIndex - 1)
e.Handled = True
ElseIf e.KeyCode = Keys.Down Then
MoveSelection(SelectedIndex + 1)
e.Handled = True
ElseIf e.KeyCode = Keys.PageUp Then
MoveSelection(SelectedIndex - 10)
e.Handled = True
ElseIf e.KeyCode = Keys.PageDown Then
MoveSelection(SelectedIndex + 10)
e.Handled = True
ElseIf e.KeyCode = Keys.Enter Then
SelectItem()
e.Handled = True
Else
MyBase.OnKeyDown(e)
End If
End Sub
Protected Overrides Sub OnLostFocus(e As EventArgs)
If Not PN.ContainsFocus Then
MyBase.OnLostFocus(e)
If Not CheckItem(Text) Then
Text = ""
End If
HideSuggestionListBox()
End If
End Sub
Protected Overrides Sub OnTextChanged(e As EventArgs)
If Not DesignMode Then
ShowSuggests()
End If
MyBase.OnTextChanged(e)
OLDText = Text
End Sub
Private Sub LS_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
If (e.KeyCode = Keys.Enter) Then
Me.SelectItem()
e.Handled = True
End If
End Sub
Private Sub LS_MouseClick(ByVal sender As Object, ByVal e As MouseEventArgs)
' select the current item
Me.SelectItem()
MsgBox(LS.SelectedItem.number)
End Sub
Private Sub LS_MouseDoubleClick(ByVal sender As Object, ByVal e As MouseEventArgs)
Me.SelectItem()
End Sub
Private Function CheckItem(ItemSTR As String) As Boolean
For Each STR As Account In ACL
If ItemSTR.ToLower = STR.ToString.ToLower Then
Return True
Exit Function
End If
Next
Return False
End Function
Private Sub MoveSelection(Index As Integer)
If Index <= -1 Then
SelectedIndex = 0
ElseIf Index > (LS.Items.Count - 1) Then
SelectedIndex = LS.Items.Count - 1
Else
SelectedIndex = Index
End If
End Sub
Private Sub ShowSuggests()
If Text.Length >= MinTypedCharacters Then
PN.SuspendLayout()
If Text.Length > 0 AndAlso OLDText = Text.Substring(0, Text.Length - 1) Then
UpdateCurrentAutoCompleteList()
ElseIf OLDText.Length > 0 AndAlso Text = OLDText.Substring(0, OLDText.Length - 1) Then
UpdateCurrentAutoCompleteList()
Else
UpdateCurrentAutoCompleteList()
End If
If Not CACL Is Nothing AndAlso CACL.Count > 0 Then
PN.Show()
PN.BringToFront()
Focus()
Else
HideSuggestionListBox()
End If
PN.ResumeLayout()
Else
HideSuggestionListBox()
End If
End Sub
Private Sub UpdateCurrentAutoCompleteList()
CACL.Clear()
For Each STR As Account In ACL
If CaseSesitivity = True Then
If STR.ToString.IndexOf(Text) > -1 Then
CACL.Add(STR)
End If
Else
If STR.ToString.ToLower.IndexOf(Text.ToLower) > -1 Then
CACL.Add(STR)
End If
End If
Next
If CACL.Count > 0 Then
UpdateListBoxItems()
Else
HideSuggestionListBox()
End If
End Sub
Private Sub UpdateListBoxItems()
If Not ParentForm Is Nothing Then
PN.Width = Width
'PN.Height = ParentForm.ClientSize.Height - Height - Location.Y
Dim F As Integer = ParentForm.ClientSize.Height - Height - Location.Y
Dim Ten As Integer = Font.Height * 10
Dim CUr As Integer = Font.Height * (CACL.Count + 1)
If F < CUr Then
PN.Height = F
ElseIf CUr < Ten Then
PN.Height = CUr
ElseIf Ten < F Then
PN.Height = Ten
Else
PN.Height = F
End If
'PN.Height = Font.Height * 10
PN.Location = Location + New Size(0, Height)
If Not ParentForm.Controls.Contains(PN) Then
ParentForm.Controls.Add(PN)
End If
CType(LS.BindingContext(CACL), CurrencyManager).Refresh()
End If
End Sub
End Class
firstly i used list(of string) before using the structure account .
the problem appears after using the structure
Any Idea about this error ?
**** additional picture show another problem after substitutes the structure with class and adds attribute.
***** changed the Structure to class
<Serializable> Public Class Account
Private Nam As String
Private Numbe As String
Public Sub New(Namee As String, Num As String)
Name = Namee
Number = Num
End Sub
Public Property Name As String
Get
Return Nam
End Get
Set(value As String)
Nam = value
End Set
End Property
Public Property Number As String
Get
Return Numbe
End Get
Set(value As String)
Numbe = value
End Set
End Property
Public Overrides Function ToString() As String
Return Name
End Function
End Class

Answer 1

Problem Resolved*
i will share the solve with you.
all the problem is coming from the line
ACL = New List(Of Account)
and the line
CACL = New List(Of Account)
because it declare new list(of account) in design time.
i solved the problem by deleting the both of line and modified the property (AutoCompleteList) to be like that.
Public WriteOnly Property AutoCompleteList As List(Of Account)
Set(value As List(Of Account))
ACL = value
CACL = New List(Of Account)
End Set
End Property
and the final code will be like that:-
the structure:
Public Structure Account
Public Name As String
Public Number As String
Public Sub New(Namee As String, Num As String)
Name = Namee
Number = Num
End Sub
Public Overrides Function ToString() As String
Return Name
End Function
End Structure
the class:
Public Class AutoCompleteTextBox
Inherits TextBox
Private ACL As List(Of Account), CACL As List(Of Account)
Private CaseSensitive As Boolean
Private MinChar As Integer
Private LS As ListBox
Private OLDText As String
Private PN As Panel
Public Sub New()
MyBase.New
MinTypedCharacters = 2
CaseSesitivity = False
LS = New ListBox
LS.Name = "SeggestionListBox"
LS.Font = Font
LS.Visible = True
PN = New Panel
PN.Visible = False
PN.Font = Font
PN.AutoSizeMode = AutoSizeMode.GrowAndShrink
PN.ClientSize = New Size(1, 1)
PN.Name = "SeggestionPanel"
PN.Padding = New Padding(0, 0, 0, 0)
PN.Margin = New Padding(0, 0, 0, 0)
PN.BackColor = Color.Transparent
PN.ForeColor = Color.Transparent
PN.PerformLayout()
If Not PN.Controls.Contains(LS) Then
PN.Controls.Add(LS)
End If
LS.Dock = DockStyle.Fill
LS.SelectionMode = SelectionMode.One
AddHandler LS.KeyDown, AddressOf LS_KeyDown
AddHandler LS.MouseClick, AddressOf LS_MouseClick
AddHandler LS.MouseDoubleClick, AddressOf LS_MouseDoubleClick
LS.DataSource = CACL
OLDText = Text
End Sub
Public WriteOnly Property AutoCompleteList As List(Of Account)
Set(value As List(Of Account))
'ACL.Clear()
ACL = value
CACL = New List(Of Account)
End Set
End Property
Public Property CaseSesitivity As Boolean
Get
Return CaseSensitive
End Get
Set(value As Boolean)
CaseSensitive = value
End Set
End Property
Public Property MinTypedCharacters As Integer
Get
Return MinChar
End Get
Set(value As Integer)
MinChar = value
End Set
End Property
Public Property SelectedIndex As Integer
Get
Return LS.SelectedIndex
End Get
Set(value As Integer)
If LS.Items.Count <> 0 Then
LS.SelectedIndex = value
End If
End Set
End Property
Private ReadOnly Property ParentForm As Form
Get
Return Me.Parent.FindForm
End Get
End Property
Public Sub HideSuggestionListBox()
If Not ParentForm Is Nothing Then
PN.Hide()
If ParentForm.Controls.Contains(PN) Then
ParentForm.Controls.Remove(PN)
End If
End If
End Sub
Private Function SelectItem() As Boolean
If LS.Items.Count > 0 AndAlso LS.SelectedIndex > -1 Then
Text = LS.SelectedItem.ToString
MsgBox(LS.SelectedItem.number)
HideSuggestionListBox()
End If
Return True
End Function
Protected Overrides Sub OnKeyDown(e As KeyEventArgs)
If e.KeyCode = Keys.Up Then
MoveSelection(SelectedIndex - 1)
e.Handled = True
ElseIf e.KeyCode = Keys.Down Then
MoveSelection(SelectedIndex + 1)
e.Handled = True
ElseIf e.KeyCode = Keys.PageUp Then
MoveSelection(SelectedIndex - 10)
e.Handled = True
ElseIf e.KeyCode = Keys.PageDown Then
MoveSelection(SelectedIndex + 10)
e.Handled = True
ElseIf e.KeyCode = Keys.Enter Then
SelectItem()
e.Handled = True
Else
MyBase.OnKeyDown(e)
End If
End Sub
Protected Overrides Sub OnLostFocus(e As EventArgs)
If Not PN.ContainsFocus Then
MyBase.OnLostFocus(e)
If Not CheckItem(Text) Then
Text = ""
End If
HideSuggestionListBox()
End If
End Sub
Protected Overrides Sub OnTextChanged(e As EventArgs)
If Not DesignMode Then
ShowSuggests()
End If
MyBase.OnTextChanged(e)
OLDText = Text
End Sub
Private Sub LS_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
If (e.KeyCode = Keys.Enter) Then
Me.SelectItem()
e.Handled = True
End If
End Sub
Private Sub LS_MouseClick(ByVal sender As Object, ByVal e As MouseEventArgs)
' select the current item
Me.SelectItem()
MsgBox(LS.SelectedItem.number)
End Sub
Private Sub LS_MouseDoubleClick(ByVal sender As Object, ByVal e As MouseEventArgs)
Me.SelectItem()
End Sub
Private Function CheckItem(ItemSTR As String) As Boolean
For Each STR As Account In ACL
If ItemSTR.ToLower = STR.ToString.ToLower Then
Return True
Exit Function
End If
Next
Return False
End Function
Private Sub MoveSelection(Index As Integer)
If Index <= -1 Then
SelectedIndex = 0
ElseIf Index > (LS.Items.Count - 1) Then
SelectedIndex = LS.Items.Count - 1
Else
SelectedIndex = Index
End If
End Sub
Private Sub ShowSuggests()
If Text.Length >= MinTypedCharacters Then
PN.SuspendLayout()
If Text.Length > 0 AndAlso OLDText = Text.Substring(0, Text.Length - 1) Then
UpdateCurrentAutoCompleteList()
ElseIf OLDText.Length > 0 AndAlso Text = OLDText.Substring(0, OLDText.Length - 1) Then
UpdateCurrentAutoCompleteList()
Else
UpdateCurrentAutoCompleteList()
End If
If Not CACL Is Nothing AndAlso CACL.Count > 0 Then
PN.Show()
PN.BringToFront()
Focus()
Else
HideSuggestionListBox()
End If
PN.ResumeLayout()
Else
HideSuggestionListBox()
End If
End Sub
Private Sub UpdateCurrentAutoCompleteList()
CACL.Clear()
For Each STR As Account In ACL
If CaseSesitivity = True Then
If STR.ToString.IndexOf(Text) > -1 Then
CACL.Add(STR)
End If
Else
If STR.ToString.ToLower.IndexOf(Text.ToLower) > -1 Then
CACL.Add(STR)
End If
End If
Next
If CACL.Count > 0 Then
UpdateListBoxItems()
Else
HideSuggestionListBox()
End If
End Sub
Sub Fill()
For Each A As Account In CACL
LS.Items.Add(A)
Next
End Sub
Private Sub UpdateListBoxItems()
If Not ParentForm Is Nothing Then
PN.Width = Width
'PN.Height = ParentForm.ClientSize.Height - Height - Location.Y
Dim F As Integer = ParentForm.ClientSize.Height - Height - Location.Y
Dim Ten As Integer = Font.Height * 10
Dim CUr As Integer = Font.Height * (CACL.Count + 1)
If F < CUr Then
PN.Height = F
ElseIf CUr < Ten Then
PN.Height = CUr
ElseIf Ten < F Then
PN.Height = Ten
Else
PN.Height = F
End If
'PN.Height = Font.Height * 10
PN.Location = Location + New Size(0, Height)
If Not ParentForm.Controls.Contains(PN) Then
ParentForm.Controls.Add(PN)
End If
Fill()
End If
End Sub
End Class
thank you all.