Javascript 跨源AJAX如何请求'；有证书'；找出要使用的cookies？

我不明白这个AJAX请求如何知道使用哪个cookie。它使用正确的一个，但是它如何知道哪一个是正确的，或者它在哪里被指定（隐式地）

当我用Chrome检查请求时，它看起来是这样的，并且它有正确的cookie集（我试图从远程主机请求登录状态的cookie集）：

答复如下：

Access-Control-Allow-Credentials:true
Access-Control-Allow-Methods:GET, POST, PATCH, PUT, DELETE, OPTIONS, HEAD
Access-Control-Allow-Origin:http://localhost:3001
Access-Control-Expose-Headers:ETag
Access-Control-Max-Age:86400
Cache-Control:no-cache
Connection:keep-alive
Content-Type:application/json; charset=utf-8
Date:Wed, 22 Mar 2017 10:18:15 GMT
Server:nginx
Set-Cookie:_foo-bar_session=SGhyWGtWTFVoc1AzUWlldmIxTjFGVXVCQU9YVkduSDFISWtLamwwT01heW5HN25saVNyYWJ1b2ZDZDI4RzNGT1BzYWZOOHNVK21DN0kxNmJRS1VDSTdwb1VVS2NtcTZ3Y1dRYUJSaTYxckpOdDZFZ2RpRlQzTHZPdDdTTjljenZzQ1hTUjlCN0RoZUlkcWlpNm5KK2VRPT0tLTkwUlNuM0Z6TDZ2TWJjZVVSUExpb0E9PQ%3D%3D--568e4688b6ff5e17faa32a3bab1a7cf01807a581; path=/; HttpOnly
Transfer-Encoding:chunked
X-Content-Type-Options:nosniff
X-Frame-Options:SAMEORIGIN
X-Request-Id:b43ce1c4-2c80-4sd5-8333-0g93ae4df940f
X-Runtime:0.013627
X-XSS-Protection:1; mode=block

---

但它怎么知道呢

除非我误解了这个问题，否则浏览器只会发回它所拥有的任何cookie，这些cookie与请求所在的域相匹配，并且与cookie中的任何

路径相匹配

有更多详细信息，以及解释浏览器如何处理cookie的文章链接。
您粘贴到问题中的标题是响应标题，对吗？它们不是请求头。至于Cookie，这只表明服务器正在为响应来自的任何域发送
Set Cookie
头。因此，当您的浏览器将另一个请求发送回该域时，它会将该域的相同cookie发送回requestAh true，抱歉。我会纠正的。但请求中的cookie是相同的。是的，就是这样。我检查cookie的方式从来没有显示域与它一起保存。那是丢失的一环！
Accept:*\/*
Accept-Encoding:gzip, deflate, sdch, br
Accept-Language:de-DE,de;q=0.8,en-US;q=0.6,en;q=0.4
Connection:keep-alive
Cookie:_foo-bar_session=WjRMdExSQ1F6UlczbER0Ui9sQU9NNllIRWo1NmpCSXo2REh6akZmM1czODZ0M29adGh4aWg3ZmdrYWdxSU5KRVptUi8ybDladmJMHJhZWKZ3A5NlJCOTdWeFpCRGJQdHVvMnlxb0VQeWlCMGRtNDkxNDF3QVdhcnVRenlsQXExa3RNEtwZ1RNMW9oaE5TV1hLbHdnPT0tLXhtYUo3YytHY2wxWTFxanlXVTJjdlE9PQ%3D%3D--b22797a9b004d0759a43f4d94686edf909610a06
Host:remote-host.de
Origin:http://localhost:3001
Referer:http://localhost:3001/de
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36

Access-Control-Allow-Credentials:true
Access-Control-Allow-Methods:GET, POST, PATCH, PUT, DELETE, OPTIONS, HEAD
Access-Control-Allow-Origin:http://localhost:3001
Access-Control-Expose-Headers:ETag
Access-Control-Max-Age:86400
Cache-Control:no-cache
Connection:keep-alive
Content-Type:application/json; charset=utf-8
Date:Wed, 22 Mar 2017 10:18:15 GMT
Server:nginx
Set-Cookie:_foo-bar_session=SGhyWGtWTFVoc1AzUWlldmIxTjFGVXVCQU9YVkduSDFISWtLamwwT01heW5HN25saVNyYWJ1b2ZDZDI4RzNGT1BzYWZOOHNVK21DN0kxNmJRS1VDSTdwb1VVS2NtcTZ3Y1dRYUJSaTYxckpOdDZFZ2RpRlQzTHZPdDdTTjljenZzQ1hTUjlCN0RoZUlkcWlpNm5KK2VRPT0tLTkwUlNuM0Z6TDZ2TWJjZVVSUExpb0E9PQ%3D%3D--568e4688b6ff5e17faa32a3bab1a7cf01807a581; path=/; HttpOnly
Transfer-Encoding:chunked
X-Content-Type-Options:nosniff
X-Frame-Options:SAMEORIGIN
X-Request-Id:b43ce1c4-2c80-4sd5-8333-0g93ae4df940f
X-Runtime:0.013627
X-XSS-Protection:1; mode=block