Prevent duplicate records when I save the values into the ComboBox - C#
<p>I have been saving into the ComboBox a value out of the selected column in datagridview with below code.
My question is:How can I prevent duplicate records when I save the values into the ComboBox? How can I do that?</p>

<p>Code:</p>

<pre><code>int ColumnIndex = dgUretimListesi.CurrentCell.ColumnIndex;          
CmbAra.Text = "";

for (int i = 0; i &lt; dgUretimListesi.Rows.Count; i++)
{
    CmbAra.Items.Add(dgUretimListesi.Rows.Cells[ColumnIndex].Value.ToString());
}
</code></pre>
