Form validation with unique email address check doesn't work

Form validation with unique email address check doesn't work

Hi, I'm enough new to JQUERY and would need some help in order to fix a form validation.

I would validate the email address is unique once the user submit the form.

In the code I developed, I receive always the message error, saying the email address in already in use, even if this is not true.

Here is my code :

JS CODE :

 $().ready(function() {

    $.validator.addMethod("verifyEmail",
        function(value, element) {

            var result = false;
            $.ajax({
                type:"POST",
                async: false,
                url: "user_unique_validator.php", // script to validate in server side
                data: {"doc-email": value},
                success: function(data) {
                    result = (data == true) ? true : false;
                }
            });
            // return true if username is exist in database
            return result;
            alert("RESULT "+result);
        },
        "Utente già in uso!"
    );
    $("#form-doctor").validate({
        rules: {
            "doc-email": {
                required: true,
                verifyEmail: true
            }
        }
    });

    // validate signup form on keyup and submit

    $("#form-doctor").submit(function( event ) {
        event.preventDefault();

       if($('#form-doctor').valid()) {
            $form = $('#form-doctor');
            data_form = new FormData($form[0]);
            $.ajax({
                type: "POST",
                processData: false,
                contentType: false,
                url:  "ajax/ajax_doctor_modificar.php",
                data: data_form,
                success: function(data) {
                    window.location.replace($('#lang').val()+'/doctor/'+data+'/');
                }
            });
        }
    });
});

PHP CODE :

<?php
require_once dirname(__FILE__) . '/ajax/login_check.php';
require_once dirname(__FILE__) . '/connections/conexion.php';
$searchVal = $_POST['doc-email'];
$myfile = fopen("testfile.txt", "w") ;



try {
    fwrite($myfile,"ERROR FOR :".$searchVal);
    $stmt = $db->prepare("SELECT email FROM doctores where email = '$searchVal'");
    $stmt->execute();
    $result = $stmt->rowCount();
    fwrite($myfile,"Result :".$result);

    if($result>0){
        $result = true;
    }else {
        $result = false;
    }
    return $result;
}
catch(PDOException $e)
{
    echo $e->getMessage();
}
fclose($myfile);
?>

HTML :

 <div class="form-group col-sm-6">
              <label class="control-label"><?php echo $array['email']?></label>
              <input name="doc-email" class="form-control required" type="text" placeholder="<?php echo $palabra['array']?>" value="<?php echo $doctores->email?>">
            </div><!-- /form-group -->