$(".sender").click(function () {

  var pwd = $("#in_pwd").val;
  var code = $("#code").val;
  
  var url = "/reset_pwd";

var xhr = new XMLHttpRequest();
xhr.open("POST", url);

xhr.setRequestHeader("accept", "application/json");
xhr.setRequestHeader("Content-Type", "application/json");

xhr.onreadystatechange = function () {
   if (xhr.readyState === 4) {
      alert('重設成功')
   }};

var data = {
  "code": code,
  "password": pwd
};

xhr.send(data);
});