* addHeader(String name,String value);  --- 針對一個key對應多個value的響應頭.
    * addDateHeader(String name,long date);
    * addIntHeader(String name,int value);

* setHeader(String name,String value);  --- 針對一個key對應一個value的響應頭.
    * setDateHeader(String name,long date);
    * setIntHeader(String name,int value);

例如:頭信息: xxx:aaa
    * addHeader(“xxx”,”bbb”);   -->xxx:aaa,bbb
    * setHeader(“xxx”,”bbb”);   -->xxx:bbb
 

1.1.3 代碼實現:
在登錄成功後的代碼上,定時的跳轉.

public class UserRefreshServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
// 解決向頁面輸出中文的亂碼問題!!!
response.setContentType("text/html;charset=UTF-8");
// 1.接收表單提交的參數.
String username = request.getParameter("username");
String password = request.getParameter("password");
// 2.封裝到實體對象中.
User user = new User();
user.setUsername(username);
user.setPassword(password);
// 3.調用業務層處理數據.
UserService userService = new UserService();
User existUser = userService.login(user);
// 4.根據處理結果顯示信息(頁面跳轉).
if(existUser == null){
// 登錄失敗
response.getWriter().println("<h1>登錄失敗:用戶名或密碼錯誤！~</h1>");
}else{
// 登錄成功
// response.getWriter().println("Login Success...");
response.getWriter().println("<h1>登錄成功!您好:"+existUser.getNickname()+"</h1>");
response.getWriter().println("<h3>頁面將在5秒後跳轉！</h3>");
response.setHeader("Refresh", "5;url=/day09/demo5-refresh/index.html");
}
} catch (Exception e) {
e.printStackTrace();
}
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}

}
 

1.1.4 總結:1.1.4.1 使用JS控制讀秒的效果.

<script type="text/javascript">
var time = 5;
window.onload = function(){
setInterval(‘changeTime()‘,1000);
}
function changeTime(){
time--;
document.getElementById("s1").innerHTML = time;
}
</script>

JavaWeb09-HTML篇筆記（三）