JQuery ajax POST calls an immediate GET to the same URL

Question

I use jQuery (1.4.2) with the Django backend and am developing with Firefox (3.5.15) on Debian. I use $ .ajax () to send some data to my server, which reflects the data back to the browser. Firefox sends a POST, and then immediately performs a GET at the same URL. Where is GET from? I do not want this to happen.

The code I use for POST is as follows:

$.ajax({
    type: 'POST',
    url: '/edit_value/',
    data: JSON.stringify(data_to_post),
    success: function(updated) {
        alert('success');
    },
    error: function(request, description, exception) {
        alert('error');
    },
    async: false,
    dataType: 'json'
});

I see a warning message, not an error message. Looking at my server logs, I correctly return data_to_post.

I looked at tcpdump and looked at the POST request. It looks as I expected:

POST /edit_value/ HTTP/1.1
Host: localhost:8000
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.15) Gecko/20101028 Iceweasel/3.5.15 (like Firefox/3.5.15)
Accept: application/json, text/javascript, */*
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-Requested-With: XMLHttpRequest
Referer: http://localhost:8000/
Content-Length: 30
Cookie: csrftoken=9e3edd79a51956f088f4a505ca1b4282; sessionid=80d72430f4682632ccfb8dc8047b7d17
Pragma: no-cache
Cache-Control: no-cache

[{"id":"161","value":"988.0"}]

The answer also looks fine:

HTTP/1.0 200 OK
Date: Mon, 22 Nov 2010 07:28:44 GMT
Server: WSGIServer/0.1 Python/2.6.6
Vary: Cookie
Content-Type: text/json

[{"id":"161","value":"988.0"}]

async true, TCP-, /. async false, / ( false). Firefox GET.

GET /edit_value/ HTTP/1.1
Host: localhost:8000
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.15) Gecko/20101028 Iceweasel/3.5.15 (like Firefox/3.5.15)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://localhost:8000/
Cookie: csrftoken=9e3edd79a51956f088f4a505ca1b4282; sessionid=80d72430f4682632ccfb8dc8047b7d17

GET? Firebug ? ?

, Craig

Answer 1

, Ajax <form>.

- , (, <form action="mypage.aspx"...), , , AJAX POST , .

, , , return false; Ajax.

Answer 2

return false; Ajax, .

, Ajax:

- Selenium

Answer 3

, false, e.PreventDefault , . , . e.preventDefault() . (: e - , )