Dynamically changing the text of items in a Winforms ComboBox

Question

I have a Winforms ComboBox that contains instances of a custom class. When the items are first added to the Items collection of the ComboBox, the

Answer 1

Thanks svick, RefreshItems() work, however as it is protected (so can only be called by a subclass) I had to do

public class RefreshingComboBox : ComboBox
{
    public new void RefreshItem(int index)
    {
        base.RefreshItem(index);
    }

    public new void RefreshItems()
    {
        base.RefreshItems();
    }
}

I have just had to do the same for a ToolStripComboBox, however it was a bit harder as you can not subclass the Combro box it contains, I did

public class RefreshingToolStripComboBox : ToolStripComboBox
{
    // We do not want "fake" selectedIndex change events etc, subclass that overide the OnIndexChanged etc
    // will have to check InOnCultureChanged them selfs
    private bool inRefresh = false;
    public bool InRefresh { get { return inRefresh; } }

    public void Refresh()
    {
        try
        {
            inRefresh = true;

            // This is harder then it shold be, as I can't get to the Refesh method that
            // is on the embebed combro box.
            //
            // I am trying to get ToString recalled on all the items
            int selectedIndex = SelectedIndex;
            object[] items = new object[Items.Count];
            Items.CopyTo(items, 0);

            Items.Clear();

            Items.AddRange(items);
            SelectedIndex = selectedIndex;
        }
        finally
        {
            inRefresh = false;
        }
    }

    protected override void OnSelectedIndexChanged(EventArgs e)
    {
        if (!inRefresh)
        {
            base.OnSelectedIndexChanged(e);
        }
    }
}

I had to do the same trip to stop unwanted events for the normal CombroBox, by overriding OnSelectedValueChanged, OnSelectedItemChanged and OnSelectedIndexChanged, as the code is the same as for the ToolStripComboBox I have not included it here.