<html>
<head>
<script>
function displayResult()
{
var x=document.getElementById("submit1").value;
alert(x);
}
</script>
</head>
<body>
<form>
Email: <input type="text" id="email">
<input type="submit" id="submit1" value="Submit form">
</form>
<button type="button" onclick="displayResult()">Display value of Submit button</button>
</body>
</html>