入门：HTML表单与Java 后台交互(复选框提交)

<form action="JavaFormTest" method="post" name="Form">
  <p>
    清输入用户名：<input type="text" name="username"/><br />
    请输入用户密码：<input type="password" name="password" /><br />
  </p>
     请选择你的课程<br />
  <p>
     <input type="checkbox" name="checkbox" value="足球" />足球
     <input type="checkbox" name="checkbox" value="篮球" /> 篮球
     <input type="checkbox" name="checkbox" value="乒乓球" />乒乓球
     <input type="checkbox" name="checkbox" value="排球" />排球球
   </p>
     <input type="button" name="but" onclick="submit()" value="提交" />
</form>

protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        PrintWriter out = response.getWriter();
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        String[] list = request.getParameterValues("checkbox");
        if (username.isEmpty())
            out.println("name is empty!<br />");
        else
            out.println("name:" + username + "<br />");

        if (password.isEmpty())
            out.println("password is empty!<br />");
        else
            out.println("password:" + password + "<br />");

        if (list == null)
            out.println("none list");
        else {
            out.println("list: <br />");
            for (int i=0;i<list.length;i++) {
                out.println("第 "+(i+1)+" 课程是："+ list[i]+"<br />");
            }
        }
    }