ajax判断用户是否可以增加一条记录

这种是比较原始的ajax用法，现在一般都是jquery、ajax一起用了，也在学习中，暂且纪念下这个比较傻逼的写法吧，这种写法不好，能不用就不用。

 

jsp里：

 

var xmlHttp;var result = false;function check() {var bookday = document.bookInsertForm.bookInsertForm_bookDay.value;var tid1 = document.bookInsertForm.bookInsertForm_tid1.value;var tid2 = document.bookInsertForm.bookInsertForm_tid2.value;var roomid = document.bookInsertForm.bookInsertForm_roomId.value;if (bookday.length == 0) {document.getElementById("bookdayDiv").innerHTML = "<font color='red'>请选择日期</font>";} else if (tid1.length == 0) {document.getElementById("tid1Div").innerHTML = "<font color='red'>请选择开始时间</font>";} else if (tid2.length == 0) {document.getElementById("tid2Div").innerHTML = "<font color='red'>请选择结束时间</font>";} else if (roomidDiv.length == 0) {document.getElementById("roomidDiv").innerHTML = "<font color='red'>请选择房间</font>";} else {document.getElementById("checkDiv").innerHTML = "<font color='red'>检测中...</font>";if (window.ActiveXObject) {xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");//IE实例} else if (window.XMLHttpRequest) {xmlHttp = new XMLHttpRequest();//其他浏览器实例}var uri = "/bookRoom/book/book!userInsertReserve.action?bookDay="+ bookday+ "&bookTimeStartId="+ tid1+ "&bookTimeEndId="+ tid2 + "&roomId=" + roomid;uri = encodeURI(uri);uri = encodeURI(uri);xmlHttp.open("post", uri, true);xmlHttp.onreadystatechange = function() {//回调函数判断当前状态是否是响应状态if (xmlHttp.readyState == 4) {if (xmlHttp.status == 200) {if (xmlHttp.responseText == "true") {document.getElementById("checkDiv").innerHTML = "<font color='red'>该时间段已经被预定啦！</font>";} else {document.getElementById("checkDiv").innerHTML = "<font color='red'>可以预定！</font>";}}}}xmlHttp.send(null);}}

 

<input type="button" value="检查" onClick="check();">
          <input type="submit" value="确认">

 

 

action:

 

/** * 用户增加预定记录 *  * @return * @throws IOException */public String userInsertReserve() throws IOException {// 获取sessionActionContext ctx = ActionContext.getContext();UserBean uBean = new UserBean();uBean = (UserBean) ctx.getSession().get("user");String s = uBean.getUserName();ReserveBean reserveBean = new ReserveBean();reserveBean.setBookDay(bookDay);reserveBean.setBookTimeEndId(bookTimeEndId);reserveBean.setBookTimeStartId(bookTimeStartId);reserveBean.setBookUserName(s);reserveBean.setRoomId(roomId);if (bookRoomService.insertReserve(reserveBean)) {clearVal();return userQueryList();}return ERROR;}/** * 判断是否可以预定，并返回结果 *  * @return * @throws IOException */public String checkReserve() throws IOException {@SuppressWarnings("unused")HttpServletRequest request = (HttpServletRequest) ActionContext.getContext().get(ServletActionContext.HTTP_REQUEST);// 获取requestHttpServletResponse response = (HttpServletResponse) ActionContext.getContext().get(ServletActionContext.HTTP_RESPONSE);ReserveBean reBean = new ReserveBean();reBean.setBookDay(bookDay);reBean.setRoomId(roomId);reBean.setBookTimeStartId(bookTimeStartId);reBean.setBookTimeEndId(bookTimeEndId);Integer count = bookRoomService.checkReserve(reBean);if (count != 0) {PrintWriter out = response.getWriter();out.print("true");out.flush();out.close();}return null;}