Stop form page load upon submit with jQuery

Question

$(document).ready(function() {
    $("form.ajax").submit(function(e) {
     destString = $(this).attr('action');
     dataString = $(this).serialize();

     $.ajax({
      type: "POST",
      url: destString,
      data: dataString,
      datatype: json,
      success: function(data) {
       if (!data.success)
       {
        $.amwnd({
         title: 'Error!',
         content: data.message,
         buttons: ['ok'],
         closer: 'ok'
        });
       }
      }
     });

     e.preventDefault();
     return false;
    });
});

That is some code I am using for making all forms I have with class="ajax" submit using Ajax. I have looked at some StackOverflow questions such as this one along with other sites on the web, which has led me put this block of code in:

e.preventDefault();
return false;

That's two things that apparently both stop the form submission via normal methods, but looks like that's not working.

The form I am testing with this is

<form action="add_comment.php" method="post" class="ajax">

Am I doing something wrong, or..?

Answer 1

datatype: json

should be

dataType: 'json'

Note:
The above fixed the form from performing default submission behaviour, doesn't guarantee the ajax call will have a proper return as I have no idea what is being returned.

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