Placed a button and named as backspace,when clicked button should act as actual backspace on a textbox

I am creating a multilanguage keyboard using vba excel 2007,I have added buttons to display the character in a textbox ,so If i want to type A then i have written code as Private Sub CommandButton88_Click() TextBox1.Text = ChrW(65) End Sub Now I have placed a button for backspace,another for enter,another for escape ,f1,etc...But how to write codes if I want the button named backspace to work exactly as backspace button in actual keyboard and enter as enter and so on....Please reply,seen keyascii and application.sendkeys({backspace}),but how to apply it on the textbox to work as backspace,enter etc...please reply,for backspace found as chr(8),but how to apply?