php - I cant load second drop down menu, when the first one is changed. The second drop down is depended on the first one -

here code, having problem displaying values of second:

html: form, first drop down elements database query.

                    <form name="farmer" action="index.php" method="post">                                     <label>                                         <span>chose land:</span>                                         <select name="land" id="land">                                             <option value="">--land--</option>                                                 <?php                                                      $sql="select `city` `lands`";                                                     $result =mysql_query($sql);                                                     while ($data=mysql_fetch_assoc($result)){                                                 ?>                                             <option value ="<?php echo $data['city'] ?>" ><?php echo $data['city'] ?></option>                                                 <?php } ?>                                         </select>                                     </label>                                  <label>                                         <span>region:</span>                                         <select name="region" id="region">                                             <option value="">--region--</option>                                         </select>                                 </label>                       <input class="button4" type="submit" name="submit" value="submit" />                  </form> 

js

        jquery(document).ready(function() {         jquery('#land').change(function() {             jquery.post(                 'getlist.json.php', {                     'land': jquery('#land').val()                 },                 function(data, textstatus) {                     jquery('#region').empty();                         if(data != null)                         {                             jquery.each(data, function(index, value) {                                 jquery('#region').append('<option value="' + value + '">' + value + '</option>');                             });                         }                         else {                             jquery('#region').append('<option value="">please select...</option>');                         }                 },                 'json'             );         });      }); 

getlist.json.php file - here make connection between region , land query(join).

<?php  mysql_connect("localhost", "root", "") or die( "unable connect database"); mysql_select_db("farmer_fields") or die( "unable select database");  if($_post && $_post['land'] != "") {      $sql="select region regions                 left join lands                 on regions.id_lands = lands.id";     $rows = array();         while ($data=mysql_fetch_assoc($sql)){             $rows['region'] = $data;                                         }     echo json_encode( $rows  ); } ?> 

no need of json here. can jquery , ajax

jquery:

function get_region(country_id) {     if (country_id != 0) {         $("#region_id").html("<option value='0'>select region</option>");         $("#region_id").prop("disabled", true);          $.post("ajax/ajax.php", {             country_id: country_id         }, function (data) {              var data_array = data.split(";");             var number_of_name = data_array.length - 1;             var value;             var text;             var opt;             var temp_array;              (var = 0; < number_of_name; i++) {                 temp_array = data_array[i].split(",");                 value = temp_array[1];                 //alert(value);                 text = temp_array[0];                 opt = new option(text, value);                 $('#region_id').append(opt);                 $(opt).text(text);             }             $("#region_id").prop("disabled", false);         });     } else {         $("#region_id").html("<option value='0'>select region</option>");         $("#region_id").prop("disabled", true);     } } 

ajax file ajax.php

if (isset($_post["country_id"])) {     $country_id = $_post["country_id"];     $region_select = mysql_query("select * region country_id='$country_id'");     $region = "";     $region_id = "";     while ($region_row = mysql_fetch_array($region_select)) {         $region = $region.$region_row["region"].         ",".$region_id.$region_row["id"].         ";";     }     echo $region; } 

html of region select box:

<select name="region_id" id="region_id" disabled="disabled">     <option value="0">select region</option> </select> 

you may change mysql_query pdo security purpose mysql_query depriciated.