Is the cookie valid for a limited time? How to set cookies? Teach you to set by hand

1.cookie Is there a valid time limit ？

cookie There is a valid time , And you can customize the effective time

2. How to set up cookie？

Here I directly encapsulate , Post code directly , If you don't understand, you can send a private message ！！！

 //  Set up cookie
  static setCookie(key, value, expiremHours) {
    var exdate = new Date();
    exdate.setTime(exdate.getTime() + expiremHours * 60 * 60 * 1000);
    document.cookie =
      key +
      "=" +
      escape(value) +
      (expiremHours == null ? "" : ";expires=" + exdate.toUTCString());
  }

  //  Read cookie
  static getCookie(key) {
    if (document.cookie.length > 0) {
      var c_start = document.cookie.indexOf(key + "=");
      if (c_start != -1) {
        c_start = c_start + key.length + 1;
        var c_end = document.cookie.indexOf(";", c_start);
        if (c_end == -1) c_end = document.cookie.length;
        return unescape(document.cookie.substring(c_start, c_end));
      }
    }
    return "";
  }

  //  Delete cookie
  static delCookie(key) {
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval = this.getCookie(key);
    if (cval != null) {
      document.cookie = key + "=" + cval + ";expires=" + exp.toUTCString();
    }
  }

  //  throttle 
  static throttle(callBack, time) {
    let timer = null;
    //timer State to be resident in memory , Here is a closure 
    return function() {
      if (!timer) {
        timer = setTimeout(() => {
          callBack();
          timer = null;
        }, time);
      }
    };
  }