If you can use jQuery you can do it like this. It's not the full code it's just to give you the idea how to start with it.
jQuery('#add').click(function(){
var memberName = jQuery('#memberName').val();
var address = jQuery('#address').val();
var designation = jQuery('#designation').val();
// Do some saving process first, using ajax and sending it to a php page on the server
// then make that php return something to validate if it's succesfully added or something
// before you show it on table. You can use ajax like
jQuery.ajax({
type: 'POST',
url: 'you php file url.php',
data: { name: memeberName, addr: address, desig: designation },
dataType: 'json', // any return type you like
succes: function(response){ // if php return a success state
jQuery('#tableID tbody').append('<tr><td>' + memberName + '</td><td>' + address + '</td><td>' + designation + '</td></tr>');
},
error: function(response){ // if error in the middle of the call
alert('Cant Add');
}
});
});
Be sure to change the id to the id you have in your html elements.
This is only on the front end side. If you have other processes like saving the newly added into the DB then you have to process that first before showing it on the table.