Code:
<html>
<body>
<form method="POST" enctype="multipart/form-data">
<input type="file" name="myfile" style="display:none" onchange="fileName=this.value">
<input type="button" value="open file" onclick="myfile.click()">
<input type="button" value="show value" onclick="alert(fileName)">
</form>
</body>
</html>
That looks like the simplest way.
