Capture keystroke using jquery.js . Download and include jquery.js before you use the code .

The code check the ASCII value of the key pressed .

$(this).keydown(function(e) {
if (e == null)
 { // for IE
 keycode = event.keyCode;
 } else {  // for mozilla
 keycode = e.which;
 }
 if(keycode == 27){ // write your custom function
 alert('Escape Pressed');
 }
});

Execute the code and press Escape to see the magic .