如何在单击时增加本地存储中的数字?

我读了 following answer 。基本上我有 button 当我点击它时,它会增加 number 在我的 localStorage span :

首次加载页面时:

$("#jikubox span").text(localStorage.length);

单击功能:

$(".save_post").on("click", function() {
  var curId = $(".my_post_id").data("id");
  $("#input_post_id").val(curId);
  localStorage.setItem("attempts", "0");
  var attempts = Number(localStorage.getItem("attempts"));
  localStorage.setItem("attempts", ++attempts);
  $("#jikubox span").text(localStorage.getItem("attempts"));
});

但如果我做了以下事情 1

console.log(localStorage.getItem("attempts"));