我应该如何从一周中“提取星期日”，然后将其作为一周的最后一天输入控制台

Question

我想从一周中提取sunday ，并且我希望在控制台中将它作为一周的最后一天，只有在我在提示中输入它之后。 如果有人可以请让我知道并纠正如何去做。

 function days(){ var daysOfWeek = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]; let currentDay = prompt("Enter day of week:"); let dayNum = daysOfWeek.indexOf(currentDay); while (dayNum < 0) { currentDay = prompt("Invalid day. Enter day of week:").toLowerCase(); dayNum = daysOfWeek.indexOf(currentDay); } let daysLeft = daysOfWeek.splice(dayNum+1).concat(daysOfWeek.splice(0, dayNum)) console.log(daysLeft); } days();

Answer 1

我不确定您要在 output 中打印什么，但我在您尝试打印的代码中看到的是一周剩余多少天。 你可以用

function days(){
  var daysOfWeek = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"];
  let currentDay = prompt("Enter day of week:");
  let dayNum = daysOfWeek.indexOf(currentDay);
  while (dayNum < 0) {
    currentDay = prompt("Invalid day. Enter day of week:").toLowerCase();
    dayNum = daysOfWeek.indexOf(currentDay);
  }
  let daysLeft = 6-daysOfWeek.indexOf(currentDay);
  console.log(daysLeft == 0 ? "last day of the week " : daysLeft);    
}
  days();

Answer 2

有很多方法可以实现这一点，我的例子使用了一个 while 循环来使用被选为迭代器的当天的键。 然后您可以将第一个值移出堆栈并返回数组中的剩余值。

如果这不是您要查找的内容，请告诉我，我可以更新或删除此答案。

 var daysOfWeek = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]; function getDaysRemaining(arr) { let currentDay = prompt("Enter day of week:") daysOfWeek.includes(currentDay.toLowerCase())? currentDay = currentDay.toLowerCase(): currentDay = prompt("Invalid day. Enter day of week:").toLowerCase() let dayKey = daysOfWeek.indexOf(currentDay) let i = 1 while (i <= dayKey) { arr.shift() i++ } return arr } console.log(getDaysRemaining(daysOfWeek))