250924_dom/05_storage2.html at main · DevCoursePracticeProjects/250924_dom · GitHub

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <form id="user">
      이름 : <input type="text" name="name" /><br />
      나이 : <input type="text" name="age" /><br />
      <button>제출</button>
    </form>
    <button id="storageClear">클리어</button>
    <button id="local">로컬</button>
    <button id="session">세션</button>
    <script>
      const userForm = document.querySelector("#user");
      const users = []; // !!!!
      userForm.addEventListener("submit", (event) => {
        event.preventDefault();
        const formData = new FormData(userForm);
        const user = {
          name: formData.get("name"),
          // 숫자
          age: Number(formData.get("age")), // Number -> 숫자로 변경
        };
        console.log(user);
        users.push(user); // !!!!
        console.log(users); // !!!!
        // localStorage.setItem("user", user); // [object Object]
        // 객체 -> 직렬화.
        localStorage.setItem("user", JSON.stringify(user));
        // localStorage.setItem("users", users); // [object Object]
        localStorage.setItem("users", JSON.stringify(users)); // !!!!
      });
      const user = localStorage.getItem("user");
      if (user) {
        const userObj = JSON.parse(user); // {"name":"김자바","age":100}
        // JSON 문자열을 -> 자바스크립트 객체로 '파싱'한다 (해석)한다
        console.log(userObj);
        console.log(JSON.parse(localStorage.getItem("users")));
      }
      const storageClear = document.querySelector("#storageClear");
      // localStorage -> 주소 기반
      storageClear.addEventListener("click", () => {
        localStorage.clear();
      });
      //   localStorage -> 자동으로 지워지지 않는 저장소
      // sessionStorage 해당 탭을 닫으면 삭제되는 저장소
      const local = document.querySelector("#local");
      const session = document.querySelector("#session");
      local.addEventListener("click", () => {
        localStorage.setItem("message", "hello");
      });
      session.addEventListener("click", () => {
        sessionStorage.setItem("message", "hello");
      });
    </script>
  </body>
</html>