[fixed] error Binding Listbox to a Collection

[superuser666]

Here's my application, whenever I delete an item from the collection, I get the error

"An unhandled exception of type 'System.ArgumentOutOfRangeException' occurred in mscorlib.dll

Additional information: Specified argument was out of the range of valid values."

Is there anything wrong with the way I delete the item ?

Public Class Form1
    Inherits System.Windows.Forms.Form
    Private mWafer As Wafer
#Region " Windows Form Designer generated code "
 
    Public Sub New()
        MyBase.New()
 
        'This call is required by the Windows Form Designer.
        InitializeComponent()
 
        'Add any initialization after the InitializeComponent() call
 
    End Sub
 
    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
 
    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer
 
    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents BtnAdd As System.Windows.Forms.Button
    Friend WithEvents btnDelete As System.Windows.Forms.Button
    Friend WithEvents lstJobs As System.Windows.Forms.ListBox
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.BtnAdd = New System.Windows.Forms.Button
        Me.btnDelete = New System.Windows.Forms.Button
        Me.lstJobs = New System.Windows.Forms.ListBox
        Me.SuspendLayout()
        '
        'BtnAdd
        '
        Me.BtnAdd.Location = New System.Drawing.Point(160, 368)
        Me.BtnAdd.Name = "BtnAdd"
        Me.BtnAdd.TabIndex = 0
        Me.BtnAdd.Text = "Add"
        '
        'btnDelete
        '
        Me.btnDelete.Location = New System.Drawing.Point(304, 368)
        Me.btnDelete.Name = "btnDelete"
        Me.btnDelete.TabIndex = 1
        Me.btnDelete.Text = "Delete"
        '
        'lstJobs
        '
        Me.lstJobs.ItemHeight = 20
        Me.lstJobs.Location = New System.Drawing.Point(8, 8)
        Me.lstJobs.Name = "lstJobs"
        Me.lstJobs.Size = New System.Drawing.Size(544, 324)
        Me.lstJobs.TabIndex = 2
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(8, 19)
        Me.ClientSize = New System.Drawing.Size(574, 450)
        Me.Controls.Add(Me.lstJobs)
        Me.Controls.Add(Me.btnDelete)
        Me.Controls.Add(Me.BtnAdd)
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)
 
    End Sub
 
#End Region
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        mWafer = New Wafer
    End Sub
 
    Private Sub BtnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnAdd.Click
        lstJobs.DataSource = Nothing
        mWafer.Add(New Job("newname"))
        lstJobs.DataSource = mWafer
        lstJobs.DisplayMember = "Name"
        lstJobs.Refresh()
    End Sub
 
    Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
        Dim curJob As Job = lstJobs.SelectedValue
        lstJobs.DataSource = Nothing
        mWafer.remove(curJob)
        lstJobs.DataSource = mWafer
    End Sub
End Class
 
Friend Class Wafer
    Inherits System.Collections.CollectionBase
 
    Public Sub Add(ByVal curDisp As Job)
 
        If Not AlreadyHaveName(curDisp.Name) Then
            Me.List.Add(curDisp)
 
            'if name is unique, then proceed to add
        Else
            'append a number to the end 
            Dim trykey As String = curDisp.Name + "#2"
 
            Dim i As Integer = 2
            While AlreadyHaveName(trykey)
                trykey = curDisp.Name + "#" + i.ToString
                i = i + 1
            End While
 
            curDisp.Name = trykey
            Me.List.Add(curDisp)
 
        End If
    End Sub
 
    Private Function AlreadyHaveName(ByVal name As String) As Boolean
        Dim contain As Boolean = False
        For Each job As Job In Me.List
            If job.Name = name Then
                contain = True
                Exit For
            End If
        Next
        Return contain
    End Function
    Public Sub remove(ByVal curDisp As Job)
        Me.List.Remove(curDisp)
    End Sub
 
    Default Public Property Item(ByVal index As Integer) As Job
        Get
            Return Me.List.Item(index)
        End Get
        Set(ByVal Value As Job)
            Me.List.Item(index) = Value
        End Set
    End Property
 
End Class
 
Friend Class Job
    Private mName As String
 
    Public Sub New(ByVal Name As String)
        mName = Name
    End Sub
    Friend Property Name() As String
        Get
            Return mName
        End Get
        Set(ByVal Value As String)
            mName = Value
        End Set
    End Property
 
    Public Shadows ReadOnly Property ToString() As String
        Get
            Return mName
        End Get
    End Property
End Class

[CyberHawke]

Your problem lies in the fact that your listbox has an item selected, so when you delete it, your project has a reference to an item that has been removed. Removing the reference will clear your problem.

Change:

Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
        Dim curJob As Job = lstJobs.SelectedValue
        [COLOR=red]lstJobs.SelectedItem = Nothing[/COLOR]
        lstJobs.DataSource = Nothing
        mWafer.remove(curJob)
        lstJobs.DataSource = mWafer
    End Sub

[superuser666]

aaah, excellent...

Thx a log, this has bogged me down for months now!