El siguiente código limita que las teclas Delete y Suprimir funcionen en un campo de entrada de texto HTML:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Block Deletion</title>
</head>
<body>
<input type='text' id='txtTest' name='txtTest' class='BlockDeletion' value='Bórrame'/>
<script src="../js/jquery-2.2.1.js"></script>
<script>
$(document).ready(function()
{
$('.BlockDeletion').on('keydown', function (e)
{
try {
if ((e.keyCode == 8 || e.keyCode == 46))
return false;
else
return true;
}
catch (Exception)
{
return false;
}
});
});
</script>
</body>
</html>