prevent lstBox item at index =0 ever to be selected

Could do something like this...

On item at listbox index 0 do the following.
1. set the following properties to False:
    IsTabStop
    IsHitTestVisible

IsHitTestVisible prevents mouse selection by preventing hit test results for the element's rendered content.
IsTabStop prevents navigating to the element by tabbing to the control or up-arrowing when the listbox has focus.

2. Handle event "SelectionChanged" on the parent listbox control and set SelectedIndex = -1 if selectedIndex = 0.

This prevents cases where the user starts typing the text of the listbox item when the listbox control has focus.  By default the listbox will autoselect the item that matches the text the user is typing.

Here is the xaml and code behind for reference:

XAML

<ListBox x:Name="mylist" HorizontalAlignment="Left" Width="Auto" SelectionChanged="mylist_SelectionChanged">
    <ListBoxItem IsTabStop="False" IsHitTestVisible="False">option 0</ListBoxItem>
    <ListBoxItem>option 1</ListBoxItem>
    <ListBoxItem>option 2</ListBoxItem>
    <ListBoxItem>option 3</ListBoxItem>
    <ListBoxItem>option 4</ListBoxItem>
</ListBox>

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Code

private void mylist_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    if (mylist.SelectedIndex == 0)
        mylist.SelectedIndex = -1;
}

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vr6r,

Sorry for the delay. The list boxes are generated on the fly:

  Dictionary<string, bool> listBoxes =   new Dictionary<string, bool>();
        listBoxes.Add("First_Name", false);
        listBoxes.Add("Last_Name", true);
        listBoxes.Add("Address", true);
        listBoxes.Add("City", true);
.
.
   private void AddListBoxes(Dictionary<string, bool> listBoxes)
    {
        Panel1.Controls.Clear();

        foreach (string box in (from listBox in listBoxes where listBox.Value select listBox.Key))
        {
              
            ListBox lb = new ListBox() { ID = "lst" + box };

            colCount += 1;
            if (colCount == colInRow + 1)
            {
                left = 50;
                top = 60 + height +50;
            }

            lb.Style["POSITION"] = "absolute";
            lb.Style["LEFT"] = left + "px";
            lb.Style["TOP"] = top + "px";
            lb.AutoPostBack=true;
            lb.DataTextField = box;
            lb.Style["Width"] = width + "px";
            lb.Style["Height"] = height + "px";
            lb.TextChanged +=new EventHandler(ListBoxSelectedIndexChanged);
            left += gap + width;
            left_old = left;
            Panel1.Controls.Add(lb);
            LoadListBoxes(lb);
        }
    }

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I am using your code like this:

  private void ListBoxSelectedIndexChanged(object sender, EventArgs e)
    {
        if (mylist.SelectedIndex == 0)
        {
              mylist.SelectedIndex = -1;
        }
         else
         {
            // some other code to be added later
         }
    }

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I have never used XAML. This will be new and exiting to learn how to apply it.

Question 1: Shall I just add an xml file and save it as XAML.xml to hold your code? How this is done?

Question 2: I possibly could include (by guesswork) how to include IsTabStop and IsHitTestVisible properties in AddListBoxes() method; but if possible at all please add them to AddListBoxes() starting on line 8, first box in this post.

Thank you,

Mike

Hi vr6r,

I stumbled to something I want to run by you. Say we have the following items in our list box:

Jack    when I a "-" in front of Jack, upon click on this item the ChangeIndex event doesn't fire
Robert
Mike

Like:

-Jack    
Robert
Mike

This basically solves the problem. I wonder if you could take a look at it. I want to know how reliable is this.

Mike