How to Use AjaxCI to enable the friend watching Function

{Code...} above is HTML {code...} above is the jquery code I wrote. The function is implemented. But why can't I see the result only when I manually refresh this page? The following CI controller is written for guidance .. {Code ...}

0) {echo 'message';}?> ">
  

Above is HTML

$ ('# Follow'). click (function () {if ($ (". follow"). text () = "follow") {var form_data = {pid:
 , Ajax: '1'}; $. ajax ({url :"
 ", Type: 'post', data: form_data, success: function (msg) {folder ('folder follow'folder .html () ;}});} else {var form_data = {pid:
 , Ajax: '1'}; $. ajax ({url :"
 ", Type: 'post', data: form_data, success: function (msg) {folder ('folder follow'folder .html (msg) ;}});} return false ;})

The above is the jquery code I wrote. The function is implemented,But why can we see the results only when we manually refresh this page?
The following CI controller is written for guidance ..

function addfollow(){    $pid = $this->input->post('pid');    if($this->input->post('ajax')){    }}

Reply content:

0) {echo 'message';}?> ">
  

Above is HTML

$ ('# Follow'). click (function () {if ($ (". follow"). text () = "follow") {var form_data = {pid:
 , Ajax: '1'}; $. ajax ({url :"
 ", Type: 'post', data: form_data, success: function (msg) {folder ('folder follow'folder .html () ;}});} else {var form_data = {pid:
 , Ajax: '1'}; $. ajax ({url :"
 ", Type: 'post', data: form_data, success: function (msg) {folder ('folder follow'folder .html (msg) ;}});} return false ;})

The above is the jquery code I wrote. The function is implemented,But why can we see the results only when we manually refresh this page?
The following CI controller is written for guidance ..

function addfollow(){    $pid = $this->input->post('pid');    if($this->input->post('ajax')){    }}

Okay, I solved the problem myself. Thanks for the prompt @ joyqi.
It is mainly because no return value is returned when data is operated, and $ ajax must be written in this way.

success:function(msg){  $('#follow').html(msg);}

# Follow returned must be a separate file

Write the CI controller as follows:

function addfollow(){$pid = $this->input->post('pid');if($this->input->post('ajax')){$data['pid'] = $pid;$this->load->view('follow', $data);}}

Your ajax returns the current number of returned results. You can see in your follow js Code.

success:function(msg){             $('#follow').html();        }

Here it should be$('#follow').html(msg);Right