Keredari - Developer's Blog

If you want to change one or two data then need to load old session variable and add new value as per your need. $userData    =   $this->session->userdata('frontend'); // old session array $userData['theme']= $this->input->post('theme'); // new value $this->session->set_userdata('frontend', $userData);

Below is the code where you can easily understand select Tag on change with ajax request using PHP. Replace id  #theme_option with yours. HTML Code <select class="form-control" id="theme_option"> <option value="default">Default</option> <option value="real-estate">Real Estate</option> <option value="dispatching">Dispatching</option> <option value="dental">Dental</option> <option value="medical">Medical</option> <option value="restaurant">Restaurant</option> <option value="consumer-product">Consumer Product</option> </select> Jquery code jQuery(document).ready(function($){     $('#theme_option').change(function(){ $.ajax({ url: "change_theme.php", data: { "theme": $("#theme_option").val() }, type: "post", su...