Question

I’m using the jQuery AJAX function in order to retrieve data from my mySQL database without having to refresh the page. I have everything in working order, my query’s are retrieving the correct data from my database. However, I am struggling to echo out an error message when no data can be retrieved based on the users input. I have a php file that provides the user interface for the user to search from, it also contains the following Scripts in the document head.

Here is what I have so far:-

<script type="text/javascript">
$(function(){
    $('#users').keyup(function(){
        var inpvalue= $('#users').val();
    });
});
</script>



<script type="text/javascript">
$(function(){
            $('#users').keyup(function(){

            var inpval=$('#users').val();

            $.ajax({
                type: 'POST',
                data: ({p : inpval}),
                url: 'data.php',
                success: function(data) {
                     $('#output_div').html(data);

          }
        });
    });
});

</script>

Any help would be greatly appreciated, sorry if I haven’t explained myself very well.

Thankyou.

Answer 1

Modify your .ajax() call so you can detect error conditions:

        $.ajax({
            type: 'POST',
            data: ({p : inpval}),
            url: 'data.php',
            success: function(data) {
                 $('#output_div').html(data);

            },
            error: function (jqXHR, textStatus, errorThrown) {
                console.log(errorThrown);
            }
        });

This is just to get you started: see http://api.jquery.com/jQuery.ajax/ for more details on what you can do with the error handler.

Of course, it’s possible that you’re getting a good HTTP status from the call, but this defensive programming will make sure.

A tool like Firebug running in your browser can also help you detect bad HTTP status code returns.