Ajax基本案例详解之$.getjson的实现

$.getJSON("doindex.jsp",{email:$("#email").val()},function(data){
         alert(data.msg);
        $("#semail").html(data.msg);
      });

String email = request.getParameter("email");
  if("2451999120@qq.com".equals(email)){
    out.print("{\"flag\":true,\"msg\":\"<font color='red'>该邮箱已注册！</font>\"}");
  }else{
    out.print("{\"flag\":false,\"msg\":\"<font color='green'>可以使用！</font>\"}");
  }