Question

Windows Forms application (c#).
I have two ComboBoxes.
If I select an item in one, I want the text in the other one to be blank.

This is what I have:

private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox2.Text = "";
}

private void ComboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox1.Text = "";
}

… but as you can see, when I make a selection in one, the text in both ComboBoxes get cleared.

How to accomplish this?

Thank you.

Answer 1

Try setting the ComboBox.SelectedIndex to -1

A zero-based index of the currently selected item. A value of negative
one (-1) is returned if no item is selected.

or rather based on your specifications try something lie

    private bool changed = false;
    private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (!changed)
        {
            changed = true;
            ComboBox2.Text = "";
            changed = false;
        }
    }

    private void ComboBox2_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (!changed)
        {
            changed = true; 
            ComboBox1.Text = "";
            changed = false;
        }            
    }