php + ajax dropdown menu

[pauloqserra]

hi there, im having a problem with a triple dropdown menu,

in firefox is working but in IE it doesnt work,

it gives me the error, "document.getElementById(...) is null and its not an object"

the line is:

if (req.status==200) {
document.getElementById(src).innerHTML=req.responseText;
}

anyone can help me out?

by the way i have this too in the code:

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;
};

[djjjozsi]

And where did you upload that code? a test url for example ? The script is missing which communicates with the php code.

there is not enough information to find the error.

hello, jjozsi.

[pauloqserra]

so here it everything that is associated with the combobox

that ajax that we put in the page(its inside of the HEAD

<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;
               } 
          }
     };
     req.open("GET", "locale.php?data="+src+"&val="+val);
     req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=utf-8"); // set Header
     req.send(null);
}

window.onLoad=dochange('categoria', -1);     

</script>

and combobox that we call in the same page

 
<?php 
		echo "<font id=categoria><select>\n";
     	echo "<option value='0'>Escolher</option> \n" ;
     	echo "</select></font>\n"; 
		?>
<?php 
		echo "<font id=subcategoria><select>\n";
     	echo "<option value='0'>Escolher</option> \n" ;
     	echo "</select></font>\n";
		?>
<?php
        echo "<font id=subcategoria2><select>\n";
     	echo "<option value='0'>Escolher</option> \n" ;
     	echo "</select></font>\n";        

		?>

and the page sossociated

<?php
    $data=$_GET['data'];
     $val=$_GET['val'];

$dbhost = "localhost";
$dbuser = "root";
$dbpass = "";
$dbname = "DB";
mysql_pconnect($dbhost,$dbuser,$dbpass) or die ("Unable to connect to MySQL server");  

 if ($data=='categoria') { 
      echo "<select name='categoria' onChange=\"dochange('subcategoria', this.value)\">\n";
      echo "<option value='0'>== Escolher ==</option>\n";
      $result=mysql_db_query($dbname,"select idcategoria,nomeCategoria from categoria");
      while(list($idcategoria, $nomeCategoria)=mysql_fetch_array($result)){
           echo "<option value=\"$idcategoria\" >$nomeCategoria</option> \n" ;
      }
 } else if ($data=='subcategoria') {
      echo "<select name='subcategoria' onChange=\"dochange('subcategoria2', this.value)\">\n";
      echo "<option value='0'>== Escolher ==</option>\n";
      $val2=$val;
      $val = substr($val,0,2);                                 
      $result=mysql_db_query($dbname,"SELECT idSubCategoria, nomeSubCategoria FROM subcategoria WHERE idcategoria='$val' order by idSubCategoria");
      while(list($id, $name)=mysql_fetch_array($result)){       
           echo "<option value=\"$id\" >$name</option> \n" ;
      }
 } else if ($data=='subcategoria2') {
      echo "<select  name='subcategoria2' >\n";
      echo "<option value='0'>== Escolher ==</option>\n";
      $val2=$val;
      $val = substr($val,0,4);
      $result=mysql_db_query($dbname,"SELECT idSubCategoria2, nomeSubCategoria2 FROM subcategoria2 WHERE idSubCategoria='$val'");
      while(list($id, $name)=mysql_fetch_array($result)){
           echo "<option value=\"$id\" >$name</option> \n" ;
      }
 }
 echo "</select>\n";  
?>

[djjjozsi]

hm..
this code is perfect for me.
i only changed the table names.

Are you sure that these substr functions needed in your code?

$val = substr($val,0,4); 

This code (maybe) designed for POST codes select.

[pauloqserra]

im not sure, its a 3rd party script. i have found the main problem
its was the WAMP i put it a "real" server and it work just fine 🙂 thanks

[scrupul0us]

doesnt JS expect the ID to be wrapped in single/dbl quotes?

if (req.status==200) {
document.getElementById('src').innerHTML=req.responseText;
} 

in my experience with JS if you dont wrap in quotes JS will think you are passing a variable called src and not a string

[djjjozsi]

Another suggestion: turn off the error reporting in your php file,

warning messages might be in that code, which can interrupt your correct output.

for example:

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

[pauloqserra]

its already turn off. and it still not working :S

[pauloqserra]

its already turn off. and it still not working :S