jsp中怎么在一个页面获取另一个页面按钮的值？

a.jsp有个按钮<inputtype="button"id="sub"value="提交“onclick="test()"/>functiontest(){varname=document.getElementById("sub").value;window.location.href="b.jsp?btnname="+name;}b.jsp获取varbtnname=request.getParameter("btnname");if(btnname==null){btnname="";}

a.jsp有个按钮function test(){var name = document.getElementById("sub").value;window.location.href = "b.jsp?btnname="+name;}b.jsp获取var btnname = request.getParameter("btnname");if(btnname==null){ btnname = ""; }