JQuery AJAX Always Success message -

Question

Regardless of what I type in my edit_data.php file, I always get a success message. I can't setup error or, in this case, success handling as it always says my variables are undefined.

How do I setup error handling if all my variables keep erroring out with undefined?

function UpdateDB() {

        // DEBUG
        alert('UPDATED DB!');

        //Hide All Alerts
        $('.alert').hide();

        //Show processing message.
        $('#processing_alert').fadeIn(1000);            

        // Run MySQL Script
        $.ajax({
          url: 'edit_data.php',

          success: function(data, status, error) {

            // IF SUCCESSFUL

            //Hide All Alerts
            $('.alert').hide();

            //Show processing message.
            $('#databaseS_alert').fadeIn(1000);
            $('#generated_msg_placehold').after('<h4>Original Request: ' + $data + '</h4>');
            $('#generated_msg_placehold').after('<h4>Status: ' + $status + '</h4>');
            $('#generated_msg_placehold').after('<h4>Error: ' + $error + '</h4>');

          },

          error: function(data, status, error) {

            // IF FAILED

            //Hide All Alerts
            $('.alert').hide();

            //Show processing message.
            $('#databaseF_alert').fadeIn(1000);
            $('#generated_msg_placehold').after('<h4>Original Request: ' + $data + '</h4>');
            $('#generated_msg_placehold').after('<h4>Status: ' + $status + '</h4>');
            $('#generated_msg_placehold').after('<h4>Error: ' + $error + '</h4>');

          }

        });     

}

Any suggestions?

Answer 1

You don't need dollar signs before variables in Javascript. That's probably why they're all coming up as undefined. Should be,

      success: function(data, status, error) {

        // IF SUCCESSFUL

        //Hide All Alerts
        $('.alert').hide();

        //Show processing message.
        $('#databaseS_alert').fadeIn(1000);
        $('#generated_msg_placehold').after('<h4>Original Request: ' + data + '</h4>');
        $('#generated_msg_placehold').after('<h4>Status: ' + status + '</h4>');
        $('#generated_msg_placehold').after('<h4>Error: ' + error + '</h4>');

      },

      error: function(data, status, error) {

        // IF FAILED

        //Hide All Alerts
        $('.alert').hide();

        //Show processing message.
        $('#databaseF_alert').fadeIn(1000);
        $('#generated_msg_placehold').after('<h4>Original Request: ' + data + '</h4>');
        $('#generated_msg_placehold').after('<h4>Status: ' + status + '</h4>');
        $('#generated_msg_placehold').after('<h4>Error: ' + error + '</h4>');

      }

Answer 2

The success/fail from the AJAX standpoint is based on the HTTP response received for the request. A 200 response is a success. So even if you PHP script sent out a message like Epic fail , unless you also modify the headers to also return some sort of error header (ie 4XX or 5XX response code), you will always engage the success handler.