Untitled

<html>
<head>
<title>サンプル</title>

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>
</head>
<body>
<script type="text/javascript">

    function CSVTEST() {
        var elem = document.getElementById("csvfile").value;
        alert(elem);

        $.get(elem, function(data){
            alert(data);
        });
    };
</script>

<input id="csvfile" type="file">
<input type="submit" value="OK" onclick="CSVTEST()">

</body>
</html>