BFE.devAI解答 - JavaScript 代码题
134. 实现Cookie

实现如下：

let myCookie = {};function install() {  Object.defineProperty(document, 'myCookie', {    get() {      let cookies = document.cookie.split("; ");      let res = "";      for (let cookie of cookies) {        if (cookie.startsWith("__myCookie_")) {          let [name, value, maxAge] = cookie.split("__myCookie_")[1].split("_");          if (maxAge && (Date.now() / 1000 > parseInt(maxAge))) {            // 如果max-age时间已经过期，就不加入cookie中            continue;          }          res += `${name}=${value}; `;        }      }      return res;    },    set(cookie) {      let [name, value] = cookie.split("=");      let options = "";      if (cookie.includes("max-age")) {        let maxAge = cookie.split("max-age=")[1].split(";")[0].trim();        options = `__myCookie_${name}_${value}_${parseInt(Date.now() / 1000) + parseInt(maxAge)}; `;      } else {        options = `__myCookie_${name}_${value}; `;      }      document.cookie += options;    }  })}function uninstall() {  delete document.myCookie;}install();

使用方法和题目中的一样，例如：

document.myCookie = 'bfe=dev';document.myCookie // "bfe=dev; "document.myCookie = 'bfe1=dev1; max-age=1';document.myCookie // "bfe=dev; bfe1=dev1; __myCookie_bfe1_dev1_1635780074; "setTimeout(() => console.log(document.myCookie), 2000); // ""

以上代码实现了题目要求的三个功能，可以通过在install()中添加其他option来扩展更多功能。