OutOfRange Exception from ArrayList

I have a ListBox and set its Datasource to an ArrayList, If I remove the last item in the ArrayList and then click on the ListBox I get an outOfRange Exception. I have copied the code which removes the item from the ArralList and error below. Any help would be greatly appreciated: Code ------ private void butRemove_Click(object sender, System.EventArgs e) { //g_InterestedPartiesArray is the ArrayList this.bChangesMade=true; BLUser blUser = new BLUser(); int nLoop=0; foreach (BLUser row in this.g_InterestedPartiesArray) { blUser=row as BLUser; if (blUser.Pid==System.Convert.ToInt32(this.lbInterestedPeople.SelectedValue)) { this.g_InterestedPartiesArray.RemoveAt(nLoop); break; } nLoop++; } //Refresh the listbox with the changed data in the ArrayList this.lbInterestedPeople.DataSource=null; this.lbInterestedPeople.DataSource=this.g_InterestedPartiesArray; this.lbInterestedPeople.DisplayMember="FullName"; this.lbInterestedPeople.ValueMember="Pid"; } Error ------ Error : Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index Source : mscorlib Stack Trace : at System.Collections.ArrayList.get_Item(Int32 index) at System.Windows.Forms.CurrencyManager.EndCurrentEdit() at System.Windows.Forms.CurrencyManager.ChangeRecordState(Int32 newPosition, Boolean validating, Boolean endCurrentEdit, Boolean firePositionChange, Boolean pullData) at System.Windows.Forms.CurrencyManager.set_Position(Int32 value) at System.Windows.Forms.ListBox.OnSelectedIndexChanged(EventArgs e) at System.Windows.Forms.ListBox.WmReflectCommand(Message& m) at System.Windows.Forms.ListBox.WndProc(Message& m) at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m) at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.SendMessage(HandleRef hWnd, Int32 msg, IntPtr wParam, IntPtr lParam) at System.Windows.Forms.Control.SendMessage(Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.Control.ReflectMessageInternal(IntPtr hWnd, Message& m) at System.Windows.Forms.Control.WmCommand(Message& m) at System.Windows.Forms.Control.WndProc(Message& m) at System.Windows.Forms.ScrollableControl.WndProc(Message& m) at System.Windows.Forms.ContainerControl.WndProc(Message& m) at System.Windows.Forms.ParkingWindow.WndProc(Message& m) at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m) at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam) at System.Windows.Forms.NativeWindow.DefWndProc(Message& m) at System.Windows.Forms.Control.DefWndProc(Message& m) at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks) at System.Windows.Forms.Control.WndProc(Message& m) at System.Windows.Forms.ListBox.WndProc(Message& m) at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m) at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) at System.Windows.Forms.ComponentManager.System.Windows.Forms.UnsafeNativeMethods+IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData) at System.Windows.Forms.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context) at System.Windows.Forms.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.RunDialog(Form form) at System.Windows.Forms.Form.ShowDialog(IWin32Window owner) at System.Windows.Forms.Form.ShowDialog() at Quest.Applic.APUpdateInternalAuditGUI..ctor(BLInternalAudit blInternalAudit, Boolean readOnly) in h:\userdata\c#\quest\quest.applic\apupdateinternalauditgui.cs:line 227 at Quest.Applic.APStartupGUI.dgAudits_DoubleClick1(Object sender, EventArgs e) in h:\userdata\c#\quest\quest.applic\apstartupgui.cs:line 1293

Hi, I had the same problem and i was searching for the answer for this. Even if the values in the arraylist and listbox were correct during the debug process, the exception occured in the application. Even it was not able to catch the exception using the events of the listbox. Final solution that i used to solve the issue was using a clone object for the arraylist. Just before reassigning the datasource of the listbox as modified arraylist, i created a new instance of the arraylist and kept the clone of the actual arraylist to it. Then, this clone arraylist object was assigned as the datasource for the listbox. Dim CloneList As New ArrayList() CloneList = ActyalArrayList.Clone() lstItems.DataSource = Nothing lstItems.Items.Clear() lstItems.DataSource = CloneUngroup Note: Before reassigning the datasource, make the datasource of the listbox to nothing and clear the items. Abhay

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mike_buffery22y ago
Same problem but used the follwing soultion. Just add the following 2 lines of code before tte refresh part of the code CurrencyManager cm = this.BindingContext[m_Elector.AbsentVoteDetails] as CurrencyManager; cm.Refresh();
abhayakumar.k22y ago
Hi, I had the same problem and i was searching for the answer for this. Even if the values in the arraylist and listbox were correct during the debug process, the exception occured in the application. Even it was not able to catch the exception using the events of the listbox. Final solution that i used to solve the issue was using a clone object for the arraylist. Just before reassigning the datasource of the listbox as modified arraylist, i created a new instance of the arraylist and kept the clone of the actual arraylist to it. Then, this clone arraylist object was assigned as the datasource for the listbox. Dim CloneList As New ArrayList() CloneList = ActyalArrayList.Clone() lstItems.DataSource = Nothing lstItems.Items.Clear() lstItems.DataSource = CloneList Note: Before reassigning the datasource, make the datasource of the listbox to nothing and clear the items. Abhay
abhayakumar.k22y ago
Hi, I had the same problem and i was searching for the answer for this. Even if the values in the arraylist and listbox were correct during the debug process, the exception occured in the application. Even it was not able to catch the exception using the events of the listbox. Final solution that i used to solve the issue was using a clone object for the arraylist. Just before reassigning the datasource of the listbox as modified arraylist, i created a new instance of the arraylist and kept the clone of the actual arraylist to it. Then, this clone arraylist object was assigned as the datasource for the listbox. Dim CloneList As New ArrayList() CloneList = ActyalArrayList.Clone() lstItems.DataSource = Nothing lstItems.Items.Clear() lstItems.DataSource = CloneUngroup Note: Before reassigning the datasource, make the datasource of the listbox to nothing and clear the items. Abhay