Question

    <script type="text/javascript">
        function bindCity() {
    // Some javascript code
                //declare options array and populate
                var modelnames = new Array();
                $.get("file.php?mt=" + qs, function(data) {
                        eval(data);
                        if(modelnames.length > 0) {
                            addOptions(modelnames);
                        }
                    }
                );
            }
        function addOptions(cl) {
            //enable child select and clear current child options
            $("#mn").removeAttr("disabled");
            $("#mn").html('');
            //repopulate child list with array from helper page
            var city = document.getElementById('mn');
            for(var i = 0; i < cl.length; i++) {
                city.options[i] = new Option(cl[i].text, cl[i].value);
            }
        }
    </script>

This is the PHP script (After getting the values to $mt):-

$SQLqueryTry = "SELECT mn FROM pd WHERE pd_mt = '$mt'";
    $SQLqueryETry = mysql_query($SQLqueryTry, $dacreint) or die(mysql_error());
    while ($Try = mysql_fetch_array($SQLqueryETry))
    {
        $output = "modelnames.push(new Option('$Try[mn]', '$Try[mn]'));\n";
    }

My output code in PHP file:-

header('Content-type: text/plain');
echo $output;

Now i am able to fetch only one value when it is $output = "modelnames.push(new Option('$Try[mn]', '$Try[mn]'));\n";

However when i add . to $output =, to make it $output .= "modelnames.push(new Option('$Try[mn]', '$Try[mn]'));\n";

I am unable to get any value. What is the problem?

Answer 1

Are you able to see any errors in your error log?

My first guess is that you’ve forgotten to initialize the $output variable before using .= on it.

Maybe try:

$output = "";
while ($Try = mysql_fetch_array($SQLqueryETry))
{
    $output .= "modelnames.push(new Option('$Try[mn]', '$Try[mn]'));\n";
}