C#

private void PopulateComboBox()
{
    for (int i = 65; i < 91; i++)
    {
        comboBox1.Items.Add(Convert.ToChar(i));
    }
}

comboBox.DataSource = {'a','b','c','d','e','f','g','h','i','j','k' ... 'z'};

public static class Alphabet {

   public static IEnumerator Lower() {
      for (char i = 'a'; i <= 'z'; i++) yield return i;
   }

   public static IEnumerator Upper() {
      for (char i = 'A'; i <= 'Z'; i++) yield return i;
   }

}

foreach (char i in Alphabet.Lower()) comboBox1.Items.Add(i);

Nitron wrote:

match a literal "$" as it's not a valid escape character...

Daniel Grunwald wrote:

So you'll have to use "\\$" or @"\$" in C#