javascript - Execute event before its natural behaviour -

is there way execute javascript-event before it's natural behaviour?

for example, using code below, if press / key on keyboard, character printed in input field, , after 2 seconds, alert showed. that's obviuos.

but there way make alert showed before / printed?

<input></input>  <script> document.queryselector("input").focus();  addeventlistener("keydown", function (e) { if (e.keycode === 191) { myfunc(e); } }); function myfunc(e) {     settimeout(function() {         alert("hello!");     }, 2000); } </script> 

unified solution inputted characters on keypress event:

addeventlistener("keypress", function(e) {   var val = e.which || e.keycode;   e.preventdefault();   myfunc(e.target, val); });  function myfunc(target, val) {   settimeout(function() {     alert("hello!");     target.value = string.fromcharcode(val);   }, 2000); } 

try it.