How to change select options depending on another input field

http://www.daniweb.com/web-development/php/code/476623/ajaxed-linked-dropdowns-select-fields-for-volatile-data

http://www.daniweb.com/web-development/php/code/475238/linked-dropdowns-select-fields-for-static-ish-data

The second may be more useful as you probably wouldn't need to update your cities table very often.

Thank you diafol, I will check those links out and let you know the results!

Thank you diafol, I will check those links out and let you know the results!

thanks for this is what i expect.
http://demos.diafol.org/ajax-linked-dropdowns.php

in localhost its working fine. but in server i got one problem the second dropdownbox is not working properly its showing last country_id values, if i click any country then that value is not chage. what can do for that ??

$stateSQL ='SELECT DISTINCT states.state_id AS value, states.state AS label FROM states WHERE states.country_id = ? ORDER BY states.state'; 

in that WHERE states.country_id = ?, what is ? means. sorry if i ask silly question.

You need to be using PDO or mysqli as it's a prepared query. The '?' is a placeholder for a parameter.

Without seeing your code, it's difficult to know what's going on.

Also - start your own thread or add to the code snippet thread:

http://www.daniweb.com/web-development/php/code/476623/ajaxed-linked-dropdowns-select-fields-for-volatile-data

Otherwise this will hijack flynismo's.

used mysqli

my html form like

<tr><td><div align="left">City:</div></td><td><select id="country" class="diafolDrop" name="city"></select></td></tr> <tr><td><div align="left">Place:</div></td><td><select id="state" class="diafolDrop" name="place" ></select></td></tr> <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script> <script src="includes/diafolatile.js"></script> <script> $('.diafolDrop').linkedDrops({ 'url' : 'includes/diadem.php', 'controls': {"country":["value","label"],"state":["value","label"]} }); </script> 

diadem.php

<?php require '../includes/diafolatile.class.php'; //Choose either PDO or mysqli (mysqli without mysqlnd driver also supported) //$db = new PDO("mysql:host=localhost;dbname=daniweb","root",""); $db = new mysqli("host","user","pass","namshimoga"); $drops = new diaFolatile($db); $countrySQL ='SELECT DISTINCT countries.country_id AS value, countries.country AS label FROM countries INNER JOIN states ON states.country_id = countries.country_id ORDER BY countries.country'; $stateSQL ='SELECT DISTINCT states.state_id AS value, states.state AS label FROM states WHERE states.country_id = ? ORDER BY states.state'; /*$citySQL = 'SELECT DISTINCT cities.city_id AS value, cities.city AS label FROM cities INNER JOIN members ON members.city_id = cities.city_id WHERE cities.state_id = ? ORDER BY cities.city';*/ /*$memberSQL = 'SELECT DISTINCT countries.country, states.state, cities.city, members.member_id AS id, members.name AS nm FROM countries INNER JOIN states ON states.country_id = countries.country_id INNER JOIN cities ON cities.state_id = states.state_id INNER JOIN members ON members.city_id = cities.city_id WHERE members.city_id = ? ORDER BY nm';*/ $drops->addItem(new diaFolItem('country', $countrySQL, 'value')); $drops->addItem(new diaFolItem('state', $stateSQL, 'value', true)); //$drops->addItem(new diaFolItem('city', $citySQL, 'value', true)); //$drops->addItem(new diaFolItem('member', $memberSQL, 'id', true)); $id = (isset($_GET['id'])) ? $_GET['id'] : NULL; $value = (isset($_GET['value'])) ? $_GET['value'] : NULL; $php_array = $drops->getData($id, $value); echo json_encode($php_array); ?> 

diafolatile.class.php

<?php class diaFolatile { private $item = array(); private $itemIds = array(); private $db; /** * * Constructor * * @param mysqli object $db */ public function __construct($db) { $this->db = $db; } /** * * Add a dropdown (diafolItem) item and create a list of ids * * @param diafolItem $diafolItem */ public function addItem(diafolItem $diafolItem) { $this->items[] = $diafolItem; $this->itemIds[] = $diafolItem->id; } /** * * Retrieve Data from DB * * @param string $id OPTIONAL - the form dropdown id (not required for first ajax call) * @param mixed $value OPTIONAL - typically the PK value (not required for first ajax call) * @return mixed[] - an array of data */ public function getData($id = NULL, $value=NULL) { if($id && in_array($id, $this->itemIds)) { $firstId = array_search($id, $this->itemIds) + 1; }else{ $firstId = 0; } $chainLength = count($this->itemIds); $output = array(); $usedItems = array(); for($i=$firstId;$i<$chainLength;$i++) { $item = $this->items[$i]; $sql = $item->sql; $stmt = $this->db->prepare($sql); if($value) $this->bind($stmt,$value); $stmt->execute(); $records = $this->fetchAllArray($stmt); if(!count($records)) { $output[$item->id]['diafolError'] = 1000; break; } $output[$item->id] = $records; $value = $records[0][$item->pkField]; } return $output; } /** * * Bind parameter to PDO or MySQLi Prepared Statement * * @param object $stmt PDOStatement or mysqli_stmt * @param mixed $value Value to be bound into prepared statement * @return mixed */ private function bind($stmt, $value) { if(get_class($stmt) == 'PDOStatement') { return $stmt->bindParam(1, $value); }elseif(get_class($stmt) == 'mysqli_stmt'){ $type = (is_int($value)) ? 'i' : 's'; return $stmt->bind_param($type, $value); } } /** * * Fetch All Results From PDO or MySQLi Prepared Statement * Takes into account lack of mysqlnd driver for mysqli * * @param object $stmt PDOStatement or mysqli_stmt * @return mixed[] - an array of all data from prepared statement */ private function fetchAllArray($stmt) { if(get_class($stmt) == 'PDOStatement') { return $stmt->fetchAll(PDO::FETCH_ASSOC); }elseif(get_class($stmt) == 'mysqli_stmt'){ if (function_exists('mysqli_get_client_stats')) { $result = $stmt->get_result(); return $result->fetch_all(MYSQLI_ASSOC); }else{ //For servers without mysqlnd driver $result = array(); $fieldList = array(); $meta = $stmt->result_metadata(); while ($field = $meta->fetch_field()) { $params[] = &$row[$field->name]; } call_user_func_array(array($stmt, 'bind_result'), $params); while ($stmt->fetch()) { foreach($row as $key => $val) { $c[$key] = $val; } $result[] = $c; } return $result; } } } } class diafolItem { public $id; public $pkField; public $where; public $sql; public function __construct($id, $sql, $PK, $where=false) { $this->id = $id; $this->pkField = $PK; $this->where = $where; $this->sql = $sql; } } 

diafolatile.js

(function($){ $.fn.linkedDrops = function(options) { var defaults = { //leave for adding functionality }; var options = $.extend({}, defaults, options); $(this).change(function(){ selectId = $(this).attr('id'); selectValue = $(this).val(); initiateSelects(selectId, selectValue); }); function initiateSelects(selectId, selectValue){ var url = options.url; if(!selectId) { id = null; value = null; }else{ id = selectId; value = selectValue; } $.getJSON(url,{id: id, value: value}, function(returnData) { $.each(returnData, function(i,v){ switch($('#' + i)[0].tagName) { case 'SELECT': insertData = createOptions(i,v); break; case 'TBODY': case 'TABLE': insertData = createRows(i,v); break; } $('#' + i).html(insertData); }); }); } function createOptions(i,v) { optionData =''; $.each(v, function(i2,v2) { optionData += "<option value='" + v2[options.controls[i][0]] + "'>" + v2[options.controls[i][1]] + "</option>"; }); return optionData; } function createRows(i,v) { rowData =''; $.each(v, function(i2,v2) { rowData +="<tr>"; for(j=0;j<Object.keys(v2).length;j++) { rowData += "<td>" + v2[options.controls[i][j]] + "</td>"; } rowData += "</tr>"; }); return rowData; } initiateSelects(); }; }(jQuery)); 

Please don't hijack threads.

Another example, courtesy of StackO oooops...
http://jsfiddle.net/GWact/

Awaiting response from flynismo or any other suggestions from contributors.

Question for flynismo: will there be multiple cities for a single zip code? I thought it would be the other way around - multiple zips for a city?