CODE EXAMPLE FOR JAVASCRIPT

window.open function

<script type="text/javascript">
function fnc1()
{
    var a=window.location.href;

    username="p";
    password=1234;
    window.open(a+'?username='+username+'&password='+password,"");

}   
</script>
<input type="button" onclick="fnc1()" />
<input type="text" id="atext"  />