我正在使用 Greasemonkey 脚本从 RSS 提要http://www.instapaper.com/folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90中提取数据并将其插入到带有 jQuery 的页面中。该地址返回有效的 RSS,但当 Greasemonkey 触发 Ajax 调用(见下文)时,它总是返回一个空请求并触发错误回调。我在 Ajax 调用中缺少什么?
$.ajax({
url: "http://www.instapaper.com/folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90",
dataType: "xml",
data: "",
type: "GET",
success: function (data){
var classString = "";
$("item",data).each(function (i) {
classString = classString + "<li><a href='" + $("link",this).text() + "'>" + $("title",this).text() + "</a></li>";
});
var message = "<div id='classes'><h2>Class Links</h2><ul>" + classString + "</ul></div>";
$("#sidelinks").prepend(message);
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
$("#sidelinks").prepend("<div id='classes'><h2>Class Links</h2><p>There was an error accessing class link information.</p></div>");
}
});
我不太确定是不是这样,但我的jQuery.ajax
调用似乎发出了与我简单地将 RSS URL 粘贴到我的位置栏时不同类型的 HTTP 调用。即使我指定请求是“GET”,jQuery 似乎正在发送“OPTIONS”请求。下面是我的 Ajax 请求发出的调用和通过在地址栏中输入 URL 的工作请求的实时 HTTP 标头捕获的输出 -
这个使用空 (?) 响应对象触发 Ajax 错误回调:
http://www.instapaper.com/folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90
OPTIONS /folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90 HTTP/1.1
Host: www.instapaper.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 (.NET CLR 3.5.30729)
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
Proxy-Connection: keep-alive
Origin: http://home.bju.edu
Access-Control-Request-Method: GET
Access-Control-Request-Headers: x-requested-with
HTTP/1.x 200 OK
Date: Thu, 27 Aug 2009 15:16:53 GMT
Server: Apache
P3P: CP="ALL ADM DEV PSAi COM OUR OTRo STP IND ONL"
Vary: Accept-Encoding
Content-Type: text/xml; charset=utf-8
Content-Length: 1210
Age: 0
这成功地在浏览器中显示数据(当我在地址栏中放置 URL 时会发生什么):
http://www.instapaper.com/folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90
GET /folder/48337/rss/11185/QBV0RZfH4KBO7GwgrR3D8b7sv90 HTTP/1.1
Host: www.instapaper.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 (.NET CLR 3.5.30729)
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
Proxy-Connection: keep-alive
HTTP/1.x 200 OK
Date: Thu, 27 Aug 2009 15:18:04 GMT
Server: Apache
P3P: CP="ALL ADM DEV PSAi COM OUR OTRo STP IND ONL"
Vary: Accept-Encoding
Content-Type: text/xml; charset=utf-8
Content-Length: 1210
Age: 0