Hi, can i ask how can i use keypress in javascript that query to my database...I already know how to use this in jquery.ajax but i just want to know how to use this in javascript.

function testsearch(){
  var querystring = document.getElementById('mystring').value;


HTML Code:
<input type="text" id="mystring" name="search" onkeypress="testsearch()">

Thank you in advance.