java script auto duplicate display 2 fileds

11:05 PM


<!DOCTYPE html>
<html>
<head>
    <style>
        
    </style>
    </head>
<body>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<input id="field_1" value=""/><br/>
<input id="field_2" value=""/>
    <script type="text/javascript">
        var $field1 = $("#field_1");
var $field2 = $("#field_2");

$field1.on("keydown",function(){
   setTimeout(checkValue,0); 
});

var v2 = $field2.val();
var checkValue = function(){
    var v1 = $field1.val();
    if (v1 != v2){
        $field2.val(v1);
        v2 = v1;
    }
};
    </script>
</body>
</html>