1.設定cookie

function setCookie(key, value, times) {
  var date = new Date();
  date.setDate(date.getDate() + times)
  document.cookie = key + '=' + value + ';expries=' + date
}

2.獲取cookie

function getCookie(key) {
  var cookies = document.cookie.split('; ');
  for (var i = 0; i <= cookies.length; i
 
++) {
    var itemCookies = cookies[i].split('=')
    if (itemCookies[0] === key) {
      return itemCookies[1]
    }
  }
}

3.刪除cookie

function delCookie(key) {
  setCookie(key, '', -1)
}