Resolved Cascading form dropdown

jawittdesigns · 10-12-2012, 01:23 PM

I trying to make a cascading dropdowns for a form

this is the JS I have

Code:

function changeSecond(first){
	var xmlhttp;
	if (window.XMLHttpRequest){// code for IE7+, Firefox, Chrome, Opera, Safari
		xmlhttp=new XMLHttpRequest();
	} else {// code for IE6, IE5
		xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
	}
	xmlhttp.onreadystatechange=function(){
		if (xmlhttp.readyState==4 && xmlhttp.status==200){
			var res=xmlhttp.responseText;
			document.getElementById("second").innerHTML=res;
		}
	}
	xmlhttp.open("GET","reservations-plane.php?first="+first,true);
	xmlhttp.send();
}

When some one makes a selection it send the value to this code. then the code (from what I understand) is supposed to populate a dropdown with the php code from reservations-plane.php passing the value to it(var first).

The value us being passed to the JS. I tested it with an alert, but it's passing the value to the code in reservations-plane.php and not populating the select on the form.

sunfighter · 10-12-2012, 03:35 PM

What you have posted for code is just the calling part of an ajax request. All we can find out from this is that you are passing the variable 'first' to reservations-plane.php and that the return from this will display in a div(maybe a div???) with an ID of "second".

What we really need to see is the file "reservations-plane.php" and maybe the div "second".

Logic Ali · 10-12-2012, 04:32 PM

The code ( if workng ) seems intended to 'populate' the element with ID "second", presumably with a string of the form

"<option value='val1'><option 1</option><option value='val2'..."

which is a hideous way populating a <select>, but should work.

There are better ways to do this. Are you responsible for the PHP and the data it generates?

jawittdesigns · 10-12-2012, 05:31 PM

Quote:

Originally Posted by sunfighter

What we really need to see is the file "reservations-plane.php" and maybe the div "second".

OK Here's the code.

PHP Code:


			
global $wpdb, $page_url;

$location= $_GET["first"];

echo $location;

$flight_sql = "SELECT ".$location." FROM wp_flr_flights GROUP BY ".$location;

$flight_result = mysql_query($flight_sql);

echo '<select name="plane_type_choose">';

while ($flt_plane_rows = mysql_fetch_row($flight_result)) {

    $plain_id = $flt_plane_rows["plane_id"];

    $plane_type = $flt_plane_rows["plane_type"];

    echo '<option value="'.$flt_plane_rows[0].'">'.$flt_plane_rows[0].'</option>';

}

echo '</select>';

and the second div

Code:

<div id="second"><select><option value=""></option></select></div>

jawittdesigns · 10-12-2012, 05:34 PM

Quote:

Originally Posted by Logic Ali

The code ( if workng ) seems intended to 'populate' the element with ID "second", presumably with a string of the form

"<option value='val1'><option 1</option><option value='val2'..."

which is a hideous way populating a <select>, but should work.

There are better ways to do this. Are you responsible for the PHP and the data it generates?

I agree it probably is a bad way of doing it, but this is for my work and I just need it to work, not to be pretty.

If I had time i'd learn to do it the right way, but I have a deadline to make.

I don't understand what you mean by "responsible" for the php.

Logic Ali · 10-12-2012, 06:13 PM

Quote:

Originally Posted by jawittdesigns

I agree it probably is a bad way of doing it, but this is for my work and I just need it to work, not to be pretty.

If I had time i'd learn to do it the right way, but I have a deadline to make.

I don't understand what you mean by "responsible" for the php.

I just meant do you know how to modify it? You need to filter that GET parameter before you're site is attacked.

You can test the PHP simply by loading the document with the right querystring parameter, so presumably it's OK.

Do you get any error messages in the console?

jawittdesigns · 10-12-2012, 06:18 PM

Quote:

Originally Posted by Logic Ali

I just meant do you know how to modify it? You need to filter that GET parameter before you're site is attacked.

You can test the PHP simply by loading the document with the right querystring parameter, so presumably it's OK.

Do you get any error messages in the console?

Oh, I haven added any sanitation yet. Right now I just want to get it working. Details come later.

No, no errors.

Logic Ali · 10-12-2012, 06:25 PM

Quote:

Originally Posted by jawittdesigns

Oh, I haven added any sanitation yet. Right now I just want to get it working. Details come later.

No, no errors.

How is the code being triggered? I don't see any event handler.

jawittdesigns · 10-12-2012, 06:31 PM

Quote:

Originally Posted by Logic Ali

How is the code being triggered? I don't see any event handler.

PHP Code:


			
$flight_sql = "SELECT DISTINCT * FROM wp_flr_flights";

$flight_result = mysql_query($flight_sql);

echo '<select name="location" id="select-location" onChange="changeSecond(this.value)">';

echo '<option value="">Select</option>';

while ($flt_loc_rows = mysql_fetch_assoc($flight_result)) {

    $loc_id = $flt_loc_rows["location_id"];

    $loc_name = $flt_loc_rows["location_name"];

    echo '<option value="'.$loc_id.'">'.$loc_name.'</option>';

}

echo '</select>';

slickuser · 10-12-2012, 06:41 PM

On a side note, this code is vulnerable to sql injection. You need to escape the $location variable or use some type of parameterized query.

http://en.wikipedia.org/wiki/SQL_injection

Quote:

Originally Posted by jawittdesigns

OK Here's the code.

PHP Code:


			
global $wpdb, $page_url;

$location= $_GET["first"];

echo $location;

$flight_sql = "SELECT ".$location." FROM wp_flr_flights GROUP BY ".$location;

$flight_result = mysql_query($flight_sql);

echo '<select name="plane_type_choose">';

while ($flt_plane_rows = mysql_fetch_row($flight_result)) {

    $plain_id = $flt_plane_rows["plane_id"];

    $plane_type = $flt_plane_rows["plane_type"];

    echo '<option value="'.$flt_plane_rows[0].'">'.$flt_plane_rows[0].'</option>';

}

echo '</select>';

Logic Ali · 10-12-2012, 08:00 PM

Presumably you have checked that the PHP is responding as expected.

If so I'd be doing some basic debugging like this:

Code:

function changeSecond(first){
        alert( "CALLED" );
	var xmlhttp;
	if (window.XMLHttpRequest){// code for IE7+, Firefox, Chrome, Opera, Safari
		xmlhttp=new XMLHttpRequest();
	} else {// code for IE6, IE5
		xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
	}
	xmlhttp.onreadystatechange=function(){
		if (xmlhttp.readyState==4 && xmlhttp.status==200){
                        alert( "DATA RETURNED" );
			var res=xmlhttp.responseText;
			document.getElementById("second").innerHTML=res;
		}
	}
	xmlhttp.open("GET","reservations-plane.php?first="+first,true);
	xmlhttp.send();
}

jawittdesigns · 10-12-2012, 09:06 PM

I got this working now.

It's something really stupid. This is a wordpress plugin and I forgot to add the extra wordpress stuff to the URL.

Code:

xmlhttp.open("GET","reservations-plane.php?first="+first,true);

should have been

Code:

xmlhttp.open("GET","<?php echo WP_PLUGIN_URL .'/'. $plugin_folder ?>/admin/reservations-plane.php?first="+first,true);