Ajax跨域请求中的Cookie问题（默认不带cookie等凭证）

var xhr = new XMLHttpRequest();
xhr.open("POST", "http://xxxx.com/demo/b/index.php", true);
xhr.withCredentials = true; //支持跨域发送cookies
xhr.send();

$.ajax({
    url: apiUrl.getCookie(‘getone‘),
    data: { age: 11 },
    xhrFields: {
        withCredentials:true  //支持附带详细信息
    },
    crossDomain:true,//请求偏向外域
    success: function (data) {
        alert(data);
    }
});

header("Access-Control-Allow-Credentials: true");
header("Access-Control-Allow-Origin: http://www.xxx.com");

  <configuration>
  <system.webServer>
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*" />
        <add name="Access-Control-Allow-Methods" value="GET, POST" />
      </customHeaders>
    </httpProtocol>
  </system.webServer>
  </configuration>