Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<body>

E-mail: <input type="email" id="myEmail">

<p>Click the button to set the email field to read-only.</p>
<p><strong>Tip:</strong> To see the effect, try to type something in the email field before and after clicking the button.</p>

<button onclick="myFunction()">Try it</button>

<p id="demo"></p>

<script>
function myFunction() {
    document.getElementById("myEmail").readOnly = true;
}
</script>
</body>
</html>