假设a站想往b站写cookie，那么目前有两种方案，参考如下：
第一种（使用jsonp）：
a站js代码如下：
$.ajax({
url: 'http://www.b.com/jsonp.jsp?domain=.b.com&value=123',
async: false,
dataType: 'jsonp',
jsonp:'callback',
jsonpCallback:"success_jsonpCallback",
success: function(result){
console.log('result======' + result.info);
},
error: function(result){
console.log('fail');
}
});
b站jsp代码如下：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="java.net.*" %>
<%
String domain = request.getParameter("domain");
String value = request.getParameter("value");
String callback = request.getParameter("callback");
// 设置 name 和 url cookie
Cookie name = new Cookie("test", value); // 设置cookie过期时间为24小时。
name.setMaxAge(60*60*24);
name.setPath("/");
name.setDomain(domain);
// 在响应头部添加cookie
response.addCookie( name );
out.write( callback + "({\"info\":\"success\"})");
%>
第二种方案：
a站页面代码：
<html>
<head>
<meta charset="utf-8">
<title>a站页面</title>
</head>
<body>
<div>
<div>
<button id = "set_cookie_btn" type="button" >写cookie</button>
</div>
<div>
<button id = "syn_cookie_btn" type="button" >同步cookie</button>
</div>
<div id="cookie_iframe">
</div>
<script src="jquery-3.2.1.min.js"></script>
<script>
(function(){
function init(){
console.log(window.location);
$('#set_cookie_btn').click(setCookie);
$('#syn_cookie_btn').click(synCookie);
} /**
* 写测试cookie
*/
function setCookie(){
document.cookie= "test=123;path=/;domain=.b.com";
} function synCookie(){
//<iframe src='http://www.b.com/setCookies.html?p=123' width='100' height='100' style="display:none"></iframe>
var value = getCookie("test");
var src = "http://www.b.com/setCookies.html?test="+value;
var iframeInfo = "<iframe src= "+src+" width='100' height='100' style='display:none'></iframe>";
$('#cookie_iframe').html(iframeInfo);
} function getCookie(cname){
var _cookies = document.cookie.split(";");
var _ran = "";
for (var i = 0; i < _cookies.length; i++) {
var _cookie = _cookies[i];
if (_cookie.split("=")[0].trim() == cname) {
_ran = _cookie.substring(_cookie.indexOf("=")+1).trim();
break;
}
}
return _ran;
}
init();
})();
</script> </body>
</html>
b站页面代码：
<html>
<head>
<meta charset="utf-8">
<title>b站页面</title>
</head>
<body>
<script src="jquery-3.2.1.min.js"></script>
<script>
var url = location.href;
var get = url.substring(url.indexOf("test"));//获取变量和变量值
var idx = get.indexOf("=");//获取变量名长度
if (idx != -1) {
var name = get.substring(0, idx);//获取变量名
var val = get.substring(idx + 1);//获取变量值
setCookie(name, val,".b.com");//创建Cookie
}
</script>
</body>
</html>