How to simplify this c# code?

Question

C++ / C#

if (e.KeyCode == Keys.A)
            {
                textBox1.Text = e.KeyCode.ToString();
            }
            if (e.KeyCode == Keys.B)
            {
                textBox1.Text = e.KeyCode.ToString();
            }
            if (e.KeyCode == Keys.C)
            {
                textBox1.Text = e.KeyCode.ToString();
            }

How can the code be lightened so as not to write every letter after Keys.Letter) ?
I saw somewhere using a for loop and signs < >

Answer 1

if(Keys.A <= e.KeyCode && e.KeyCode <= Keys.Z)
  textBox1.Text = e.KeyCode.ToString();

And where is the for loop to use - xs.