Ajax带烧瓶-seasurf调用

I am developing a small app on localhost and using flask-seasurf to prevent csrf attacks. All my non-ajax forms work correctly with flask-seasurf. I have one form that triggers an ajax call to '/checkajax' on form submit; this worked until I started to use flask-seasurf but now I get a console error and the ajax doesn't work:

Warning in flask_seasurf: Forbidden (CSRF token missing or incorrect): /checkajax 

The form triggering the ajax call has the standard hidden field containing the 'csrf_token()' function call of flask-seasurf embedded in the jinja page template:

<input id="csrf-token" type="hidden" name="_csrf_token" value="{{ csrf_token() }}">

The ajax call structure is:

$("#submit").submit(function(event) {
    event.preventDefault();
    $.ajax({
        url: "/checkajax",
        data: {...},
        type: "POST",
        datatype: "text",
        success: function(response){
            ...
        },
        error: function(response) {
            ...
        }
    });
});

I can see from the site cookie that there is an entry for '_csrf_token' generated by flask-seasurf. Can anyone give some insight as to why this ajax call is now not working?

The solution to my problem was to modify the header of the ajax call to include X-CSRFToken defined as the flask-seasurf token from my form:

var csrf_token = $("csrf-token").val()

$("#submit").submit(function(event) {
    event.preventDefault();
    $.ajax({
        headers: {"X-CSRFToken", csrf_token},
        url: "/checkajax",
        data: {...},
        type: "POST",
        datatype: "text",
        success: function(response){
            ...
        },
        error: function(response) {
            ...
        }
    });
});

Hope that helps someone else.