<html>
<head>
<script>
function myFunction()
{
var select = document.getElementById("myselect");
var x = select.value; // Get selected value
if (x === "Select Subject")
{
alert("Please select a subject.");
}
else
{
document.getElementById("demo").innerHTML = "You selected: " + x;
}
}
</script>
</head>
<body>
<br><br><br>
<p>Floating menu. Scroll Down.</p>
<select id="myselect" style="position: fixed;">
<option value="Select Subject"> Select Subject </option>
<option value="OOP"> OOP </option>
<option value="CG"> CG </option>
<option value="DBMS"> DBMS </option>
<option value="DSU"> DSU </option>
<option value="DTE"> DTE </option>
</select>
<br> <br>
<input type="button" value="Submit" onclick="myFunction()">
<br> <br>
<p id="demo"></p>
</body>
</html>
