JavaScript獲取某一天所在的星期

function getWeekStartAndEnd() {
 const oneDayTime = 1000 * 60 * 60 * 24; // 一天里一共的毫秒數(shù)
 const today = new Date();
 const todayDay = today.getDay(); // 獲取今天是星期幾，假設(shè)是周3
 const startDate = new Date(
 today.getTime() - oneDayTime * (todayDay - 1)
 );
 const endDate = new Date(today.getTime() + oneDayTime * (7 - todayDay));

 return { startDate, endDate };
}
const week = getWeekStartAndEnd();
console.log(week.startDate, week.endDate);

function getWeekStartAndEnd(timestamp) {
 const oneDayTime = 1000 * 60 * 60 * 24; // 一天里一共的毫秒數(shù)
 const today = timestamp ? new Date(timestamp) : new Date();
 const todayDay = today.getDay() || 7; // 若那一天是周末時(shí)，則強(qiáng)制賦值為7
 const startDate = new Date(
 today.getTime() - oneDayTime * (todayDay - 1)
 );
 const endDate = new Date(today.getTime() + oneDayTime * (7 - todayDay));

 return { startDate, endDate };
}

function getAllWeekToday() {
 const oneDayTime = 1000 * 60 * 60 * 24;
 const today = new Date();
 const todayDay = today.getDay() || 7; // 若那一天是周末時(shí)，則強(qiáng)制賦值為7
 const startDate = new Date(
 today.getTime() - oneDayTime * (todayDay - 1)
 );
 let dateList = [startDate];

 for (let i = 1; i < 7; i++) {
 dateList.push(new Date(startDate.getTime() + oneDayTime * i));
 }
 return dateList;
}