[theighost]

i am using code igniter in the website i'm working on and i need php combined with any language to do:

for example i have a dropdown list named states that takes its values from a data base, and i have another dropdown list named cities that has its values from a database also.

when i click on a state the city dropdown list should show the cities in that state only.

i read that i need ajax...which i dont know hot to use

any hints or scripts?

[phillyhotshots]

1. Create Dropdown Menu (state_dropdown.php)

Code:

<?     
     echo "<form name=sel>\n";
     echo "States : <font id=states><select>\n";
     echo "<option value='0'>============</option> \n" ;
     echo "</select></font>\n";
     
     echo "Cities : <font id=cities><select>\n";
     echo "<option value='0'>=== none ===</option> \n" ;
     echo "</select></font>\n";
?>

<script language=Javascript>
function Inint_AJAX() {
try { return new ActiveXObject("Msxml2.XMLHTTP");  } catch(e) {} //IE
try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch(e) {} //IE
try { return new XMLHttpRequest();          } catch(e) {} //Native Javascript
alert("XMLHttpRequest not supported");
return null;
};

function dochange(src, val) {
var req = Inint_AJAX();
req.onreadystatechange = function () {
 if (req.readyState==4) {
      if (req.status==200) {
           document.getElementById(src).innerHTML=req.responseText; //retuen value
      }
 }
};
req.open("GET", "state.php?data="+src+"&val="+val); //make connection
req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=iso-8859-1"); // set Header
req.send(null); //send value
}

window.onLoad=dochange('states', -1);         // value in first dropdown
</script>

2. Select States and Cities to Show in Dropdown (state.php)

Code:

<?
//set IE read from page only not read from cache
header ("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header ("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header ("Cache-Control: no-cache, must-revalidate");
header ("Pragma: no-cache");

header("content-type: application/x-javascript; charset=tis-620");

$data=$_GET['data'];
$val=$_GET['val'];

//set database
$dbhost = "localhost";
$dbuser = "";
$dbpass = "";
$dbname    = "test";
mysql_pconnect($dbhost,$dbuser,$dbpass) or die ("Unable to connect to MySQL server");

if ($data=='states') {  // first dropdown
  echo "<select name='states' onChange=\"dochange('cities', this.value)\">\n";
  echo "<option value='0'>==== choose state ====</option>\n";
  $result=mysql_db_query($dbname,"select `id`, `state` from states order by `state`");
  while(list($id, $name)=mysql_fetch_array($result)){
       echo "<option value=\"$id\" >$name</option> \n" ;
  }
} else if ($data=='cities') { // second dropdown
  echo "<select name='cities' >\n";
  echo "<option value='0'>====choose cities ====</option>\n";                   
  $result=mysql_db_query($dbname,"SELECT `id`, `city` FROM cities WHERE `state_id` = '$val' ORDER BY `city` ");
  while(list($id, $name)=mysql_fetch_array($result)){
       echo "<option value=\"$id\" >$name</option> \n" ;
  }
}
echo "</select>\n";
?>

Example:http://superkeng.freehyperspace.com/state_dropdown.php
Download Source:http://www.megashare.com/233052

[theighost]

much appreciated that helps

[phillyhotshots]

No problem, hope it works for you!