javascript - Prevent browser(Chrome) to run default functions like scroll with space -

i have used 2 functins here first 1 blocking default feature space bar scroll,etc

<span id="current"></span>  $("html").on("keydown", function (e) {   {         e.preventdefault();   } }); document.onkeypress = function(evt)  {      evt = evt || window.event;     var charcode = evt.keycode || evt.which;     document.getelementbyid("current").innerhtml=charcode; }; 

now code works in firefox blocking various default functions of firefox ctrl+a ctrl+s space bar scroll , gives output in span when tried in chrome ,it blocks various default functions of chrome didn't give output in span.

i can write as

document.onkeypress = function(evt)  {      evt = evt || window.event;      var charcode = evt.keycode || evt.which;      document.getelementbyid("current").innerhtml=charcode;      return false; }; 

it worked both firfox , chrome function(evt) long , contain many if-else loops , if press double space or press space bar continously scrolls down want alternative solution in can use 2 functions 1 blocking , other outputs , work in chrome.

 function (x) {   {     x = window.event;     var cc = evt.keycode ;     $('#current').html=cc;     x.preventdefault();     return false;   } });