通过js让<select></select>标签动态设置默认值

<select id="selectY" name="job" onchange="javascript:location.href=this.value;"><option value="searchUserinfo.action?job_value=0">所有用户</option><option value="searchUserinfo.action?job_value=10010">java工程师</option><option value="searchUserinfo.action?job_value=10011" >c开发工程师</option><option value="searchUserinfo.action?job_value=10012" >web前端工程师</option></select><input id="option_num" type="hidden" value="<s:property value="#session.option_num"/>"><script>     var i=document.getElementById("option_num").value;     var select=document.getElementById("selectY");     var arr=select.getElementsByTagName("option");     arr[i].selected="selected";</script>

在action中：

Map<String, Object> session=ActionContext.getContext().getSession();session.put("option_num","1");//0-3