replace keycode cross browser

replace keycode cross browser

Hi
I want to handle keyboard and want to replace keycodes like when user enter / press key a = 65 I may able to change and show in textbox b= 66.

for internet explorer I have script like 

function InputEventKeyPress(event){
window.event.keyCode  = changecode(window.event.keyCode);
}

function  changecode(c){

switch (c){
//CAPITAL LETTERS A - Z 
case 65 : return 66; break; //A
case 66 : return 67; break; //B
case 67 : return 68; break; //C
case 68 : return 69; break; //D
case 69 : return 70; break; //E
case 70 : return 65; break; //F

}