使用jQuery将访问控制请求标头添加到AJAX请求的标头中

我想向jQuery的AJAX POST请求添加自定义标头.

I would like to add a custom header to an AJAX POST request from jQuery.

我已经尝试过:

$.ajax({
    type: 'POST',
    url: url,
    headers: {
        "My-First-Header":"first value",
        "My-Second-Header":"second value"
    }
    //OR
    //beforeSend: function(xhr) { 
    //  xhr.setRequestHeader("My-First-Header", "first value"); 
    //  xhr.setRequestHeader("My-Second-Header", "second value"); 
    //}
}).done(function(data) { 
    alert(data);
});

当我发送此请求并使用FireBug观看时，看到以下标头:

When I send this request and I watch with FireBug, I see this header:

选项xxxx/yyyy HTTP/1.1
主持人:127.0.0.1:6666
用户代理:Mozilla/5.0(Windows NT 6.1; WOW64; rv:11.0)Gecko/20100101 Firefox/11.0
接受:text/html，application/xhtml + xml，application/xml; q = 0.9，/; q = 0.8
接受语言:fr，fr-fr; q = 0.8，en-us; q = 0.5，en; q = 0.3
接受编码:gzip，deflate
连接:保持活动状态
来源:null
访问控制请求方法:POST
访问控制请求标头:我的第一标头，我的第二标头
语法:无缓存
缓存控制:无缓存

OPTIONS xxxx/yyyy HTTP/1.1
Host: 127.0.0.1:6666
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:11.0) Gecko/20100101 Firefox/11.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,/;q=0.8
Accept-Language: fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Connection: keep-alive
Origin: null
Access-Control-Request-Method: POST
Access-Control-Request-Headers: my-first-header,my-second-header
Pragma: no-cache
Cache-Control: no-cache

为什么我的自定义标头转到Access-Control-Request-Headers:

Why do my custom headers go to Access-Control-Request-Headers:

访问控制请求标头:我的第一个标头，我的第二个标头

Access-Control-Request-Headers: my-first-header,my-second-header

我期望这样的标头值:

My-First-Header:第一个值
My-Second-Header:第二个值

My-First-Header: first value
My-Second-Header: second value

有可能吗?