document.writeln(location.protocol);
document.writeln(location.origin); //包括端口号
document.writeln(location.host); //不包括端口号
document.writeln(location.port);
//默认为80的就为空
document.writeln(location.pathname);
<a href="<%=location.origin%>/membership/member/detail?member_id=<%= item.member_id %>">