Question

My JS function expects a certain return from the PHP code in case of a failure.

function showResult(data) 
{
    if (data == 'save_failed') {
        document.getElementById('result').innerHTML = 'Unfortunately, we were not able to save your information. Please contact an admin.';
        return false;
    } else {
        $("#notify").clearForm().clearFields().resetForm();
        document.getElementById('result').innerHTML = 'Thank you for signing up with us.';
        return false;
    }
}

This works fin when I echo 'save_failed'; in case of an explicit error, but it does not work in the case of die statements, such as this one:

mysql_connect("host", "user", "pass") or die('save_failed');

I entered a wrong hostname but the JS function did not receive the 'save_failed' return.

PHP script:

if (!(empty($_POST['name']) && empty($_POST['email'])))
    {
        //sanitizing inputs for MySQL insertion
        $name = mysql_real_escape_string($_POST['name']);
        $email = mysql_real_escape_string($_POST['email']);

        //connecting to db
        mysql_connect("host", "user", "pass") or die('save_failed');
        mysql_select_db("table") or die('save_failed');

        //inserting into table
        mysql_query("INSERT INTO notify (name, email) VALUES('" . $name . "', '" . $email . "' ) ") 
        or die('save_failed');  

    }
    else
    {
        echo 'save_failed';
    }

Answer 1

Even though die("save_failed") will output “save_failed”, it will not stop any previous output in your script from being sent.

Ensure that if you go to the script yourself then you are receiving just “save_failed” in the page source and no erroneous characters