获取url js更改元素class属性

获取整个url

var search = window.location.href

从url中获取参数(?key=value)

var search = window.location.search

跳转页面时 依据url更改下拉菜单class属性 实现展开下拉菜单选中当前操作

if(window.location.href.indexOf("select_book.jsp")>=0)
        {
            select_Li=document.getElementById("select_Li")
            select_Li.className="mm-active"

            select_a=document.getElementById("select_a")
            select_a.className="has-arrow waves-effect aria-expanded=true"

            select_ul=document.getElementById("select_ul")
            select_ul.className="sub-menu mm-collapse mm-show aria-expanded='false'"
        }

<li id="select_Li">
                    <a id="select_a" href="javascript: void(0);" class="has-arrow waves-effect"><span>查找图书</span></a>
                    <ul id="select_ul" class="sub-menu mm-collapse" aria-expanded="false">
                        <li id="all"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=all">全部</a></li>
                        <li id="sanwen"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=sanwen">散文</a></li>
                        <li id="suibi"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=suibi">随笔</a></li>
                        <li id="xiaoshuo"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=xiaoshuo">小说</a></li>
                        <li id="kepu"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=kepu">科普</a></li>
                        <li id="biancheng"><a href="${pageContext.request.contextPath}/user/select_book.jsp?opr=biancheng">编程</a></li>
                    </ul>
  </li>