login
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//设置编码
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();//服务器到浏览器写出
//用servlet写登录页面
out.print("<form action='"+request.getContextPath()+"/servlet/doLogin' method=''>");
out.print("用户名：<input type='text' name='username'><br/>");
out.print("密码：<input type='password' name='password'><br/>");
out.print("<input type='checkbox' name='remember'>记住用户名<br/>"); //remember 记住密码
out.print("<input type='submit' value='登录'>");
out.print("</form>");
}
dologin
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();//服务器到浏览器写出
//1.获取前端数据
String username = request.getParameter("username");
String password = request.getParameter("password");
//2.处理业务逻辑
if("admin".equals(username)&&"123456".equals(password)){
out.print("登录成功");
}else{
//3.分发转向
out.print("登录失败"); // 2秒后 重定向路径 动态获取项目名
response.setHeader("refresh", "2;url="+request.getContextPath()+"/servlet/login");
}
}
login
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//设置编码
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();//服务器到浏览器写出
//+++
String username="";
String checked="";
Cookie[] cookies=request.getCookies();
for(int i=0;cookies!=null&&i<cookies.length;i++){
if("username".equals(cookies[i].getName())){ //getname
username = cookies[i].getValue(); // getvalue (name,value)
checked="checked='checked'";
}
}
//用servlet写登录页面
out.print("<form action='"+request.getContextPath()+"/servlet/doLogin' method=''>");
out.print("用户名：<input type='text' name='username' value='"+username+"'><br/>");
out.print("密码：<input type='password' name='password'><br/>");
out.print("<input type='checkbox' name='remember' value='"+checked+"'>记住用户名<br/>"); //remember 记住密码
out.print("<input type='submit' value='登录'>");
out.print("</form>");
}
dologin
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();//服务器到浏览器写出
//1.获取前端数据
String username = request.getParameter("username");
String password = request.getParameter("password");
//++1
String remember=request.getParameter("remember");
//++2 创建一个cookie
Cookie cookie=new Cookie("username",username);
//2.处理业务逻辑
if("admin".equals(username)&&"123456".equals(password)){
//登陆成功后选择是否记录用户名
if(remember!=null){ //checkbox 不打√ null
//记住用户名
cookie.setMaxAge(Integer.MAX_VALUE); //设置cookie保存时间
}else{
cookie.setMaxAge(0); //清除cookie
//回写到客户端
response.addCookie(cookie);
}
out.print("登录成功");
}else{
//3.分发转向
out.print("登录失败"); // 2秒后 重定向路径 动态获取项目名
response.setHeader("refresh", "2;url="+request.getContextPath()+"/servlet/login");
}
}