function click() {
if (event.button==2||event.button==3) {
oncontextmenu='return false';
}
}
function keypresed() {
var tecla = window.event.keyCode;
   if(tecla==17){
       return false;
   }
}

document.onkeydown=keypresed;
document.onmousedown=click
document.oncontextmenu = new Function("return false;")