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Bound ComboBox not matching

I'm new to C# but not to programming. I've been toying around with VS, becoming more comfortable with the language and got stuck on a combobox bound to an int datatable column of an in-memory dataset.
I worked on a DataGridView and had no problems creating a DataGridViewComboBoxColumn and populating its dropdown list using a custom class comprised of Key:int and Desc:string. ValueMember = Key, DisplayMember = Desc. DataSource is left as null since the list is directly built into the ComboBox. Pick from the combobox and save changes works fine in the grid.
Then I moved to a ComboBox. Both the grid and the ComboBox have the exact same BindingSource. So yes they point to the same row at the same time.
I bind the ComboBox with:
cbCtrl.DataBindings.Add( "Text", myBindingSource, ColDBName );
Without populating the dropdown items of the ComboBox, I see the raw int value show up in the ComboBox. I change rows using the grid and the ComboBox value changes too. So it's good.
Then I populate the dropdown list of items in the ComboBox (the same as the grid's column tied to the same column) and it's trouble. The raw int value (eg 19) does not get matched to the proper "Key" item in the dropdown list of the ComboBox. I've tried DropDownStyle = DropDown & DropDownList but no luck with either. And I've looked for hours trying to find a fix. There are no events hooked up to the ComboBox. I expected automatic hookup of the raw value to the matching "Key" item in the ComboBox's dropdown list.
Is there something else to hook up? Frustrating since I expect something minor.
Any help would be Greatly appreciated. Thank you.
*Edit: The dropdown list actually comes from a populated BindingList<> and the BindingList<> is supplied as the ComboBox.DataSource.

I finally stumbled upon the answer:
cbCtrl.DataBindings.Add( "SelectedValue", myBindingSource, ColDBName );
That's all I needed. I got it from a great article
http://www.codeproject.com/Articles/24656/A-Detailed-Data-Binding-Tutorial?msg=5325959#xx5325959xx

Displaying a value in a populated combo box

Here is the situation:
I have populated a combo box with the names of divisions in my company and it is working fine. I go into edit mode and pull one record out of the data table so I bind all controls on the form with one record. I also populate this combo box with all divisions but want it to display the selected division. While I know how to display correct date in textbox controls, I do not know how to make combo box display only selected data. It displays the first record from the query which populates it. Any suggestions?
Thanks

Not clear if you are using ASP.NET or Windows Form. I am assuming Windows Form at the moment since it has an actual ComboBox control, while ASP.NET only has DropDownList (not counting the AJAX Control Toolkit).
ComboBox has a bunch of Selected... properties, i.e. SelectedIndex, SelectedItem, SelectedValue, SelectedText that you can manipulate (set) to show a certain item on the screen. So you can just do cbDivision.SelectedText = myRecord.Division (assuming Division in myRecord contains the same name as the one bound in the ComboBox.
for reference, see: this

I'm not sure I understood your question correctly. But I think you just want to display the selectedValue in the dropdown list populated from a list of values.
< asp:DropDownList DataTextField="SomeDecsription" DataValueField="SomeValue" ...... />
I apologise if this is not what you were asking for

WinForms, BindingSource, prevent CurrentItem change

How can I prevent bindingSource Current item from changing?
(there is no changing event with cancel argument...)
This is scenario:
I have a dataGridView, and text-boxes on the same form.
I am using text-boxes to change values in the datasource (with standard databinding)
Bindings are written manually (After save button is clicked)
When user selects another row using DataGridView, bindingSource.Current propery is changed, and text boxes are updated with values from selected row. Changes that user entered are lost.
Is there any way to prevent this problem?
Can I prevent bindingSource.Current property from changing?
Is there any better option to prevent this behaviour?
(disabling dataGridView is unfortinutelly not an option)

It sounds like you don't want to not change bindingSource.Current, but rather you want to save the contents of the text boxes before you change the current row? If you've bound a collection to the bindingSource, then don't the text boxes refer to properties in the current element in that collection?
I'm not really sure what you're trying to do, but a shot in the dark might be to bind the same DataSource to two different BindingSource objects, something like this:
gridBindingSource.DataSource = theDataSource;
textBoxBindingSource.DataSource = theDataSource;
myDataGrid.DataSource = gridBindingSource;
firstNameTextBox.Bindings.Add (new Binding ("Text", textBoxBindingSource, "FirstName"));
but this would be weird, because if theDataSource is appropriate for a grid control, then it's a collection of things that have a FirstName property. Maybe if you were more specific in your question.
ETA: If you want to save the text box contents to the current row, call ValidateChildren () on the container before the bindingSource.Current property changes.

I have a somewhat similar framework with both grid and textboxes on same form. When user clicks the EDIT button (or Add), I just disable the gridview control itself...
MyDataGrid.Enabled = false;
continue editing..
Then in the SAVE, if all is ok,
MyDataGrid.Enabled = true;

How do I create an editable databound combo box in a DataGrid in WinForm?

I have a noob question.
I have a WinForm (.net 2.0 in VS 2008) on my form I have a DataGrid. One of the fields in that DataGrid is a combo box that is bound to a separate table. This works, but I am unable to edit or add. I cannot add a value that is not on the list.
I want to create a lookup box (for lack of a better term).
The form is for Parts Order Entry. In the DataGrid Data Source is PartsOrder_table, the Work order Field is an int in the PartsOrder_table, and the combo box is bound to the WorkOrder_table. The WorkOPRder_Table has WorkOrd_ID int and WrkOrd nvarchar(10)
The Combo Box Data Source is WorkOrd_Table Display Member is WorkOrd Value Member is WorkOrder_ID.
This works great with the problem that I cannot add or select anything not in WorkOrder_table.
Any help would be greatly appreciated.

Seems you cannot in a straight forward manner. This thread shows a way of doing this, by adding the needed values during the Validation of the ComboBox control. See the URL for more details.
http://social.msdn.microsoft.com/forums/en-US/winformsdatacontrols/thread/31a28e99-6f9f-4cce-b256-9b7cf1ddf69a/

How to remove selected items from ListBox when a DataSource is assigned to it in C#?

How to remove selected items from ListBox when a datasource is assigned to it in C#?
When trying to remove, got error
"Items collection cannot be modified when the DataSource property is set."
But when i try to remove item from datasource (datatable) ,
it thorws error as "datarow is not in current row collection".

Find that item in the DataSource object and remove it, then re-bind the ListBox.
EDIT:
Here's how you delete from a DataTable as your DataSource, regardless of the .NET version.
DataRowView rowView = listBox.SelectedItem as DataRowView;
if (null == rowView)
{
return;
}
dt.Rows.Remove(rowView.Row);
I haven't tried with anything other than WinForms DataGridViews, but I highly recommend BindingListView, which is both faster than DataTables/Views and allows you to bind generic List<T>s as your DataSource.

Alternatively, use a list that implements IBindingList or inherits from BindingList. When objects are added or removed from a Binding List, any controls bound to it are automatically notified of the change and will update themselves accordingly. If you are using BindingList and your class also implements INotifyProperty changed, Any changes to class properties will also be updated automatically in the databinding control. For example, if a column in a datagrid(view) is bound to a property, "Name", and you change "Name" in the datasource, the datagrid will automatically update. If you add a new item to the datasource, the datagrid will update automatically. Binding List also supports notification in the other direction. If a user edits the "Name" field ina datagrid, the bound object will be updated automatically. Going off topic slightly, if you go a little further and impliment "SupportsSortingCore" and the associated methods in BindingList, you can add automatic sorting to your data. Clicking on a columnm header will automatically sort the list and display the header sort direction arrow.

If the ListBox has a datasource assigned, you must remove items from the datasource and then rebind the ListBox

You need to modify the data source rather than the Items collection of the control. Depending on what kind of data source you are binding to, there are going to be different things you have to do so that your UI updates.
The best way is find a collection that fits your needs and implements IBindingList or IBindingListView. Those two interfaces implement even handlers that listen for a CollectionChanged event and update your UI accordingly.
If your collection doesn't support those interfaces, you're going to have to re-bind your data source every time somebody adds/removes an item.

when you get the message "Items collection cannot be modified when the DataSource property is set."
setting the datasource to something else, empty list or null does not help when
the code initializecomponent is not completed.
to avoid that error, one must do the change of datasource or the item list during or after form load.
I know it does not seem to make sense. Hoever, the visual studio designer will generate code in the form designer.cs or vb that will add items to the listbox if any code that changes the items is found before end of initialize components

While Chris Doggett posted a valid solution, I ran into problems while using it. By using that method it was not allowing a subsequent GetChanges(DataRowState.Deleted) to work properly.
To better solve my problem, I only had to change a single line - the last line.
DataRowView rowView = listBox.SelectedItem as DataRowView;
if (null == rowView)
{
return;
}
rowView.Row.Delete();
This allowed my GetChanges call to work properly.

This worked for me
DataTable temp = (DataTable)lstBlocks.DataSource;
temp.Rows.RemoveAt(position);

its vary simple , assign a new blank value to listbox
eg..
Dim ABC As New List(Of String)()
ListBox1.DataSource = ABC

ListBox implementation is bugged, you need to create a new data source instance for the component for it to recognize a change.
Eg:
ActivitiesList.DataSource = _activities;
_activities = new List<Activity>(_activities);
_activities.Remove((Activity)ActivitiesList.SelectedItem);
ActivitiesList.DataSource = _activities;