返回周几的名称 (不是一个数字) - 在线编辑器

          <p id="demo">单击按钮显示今天周几</p>
<button onclick="myFunction()">点我</button>
<script>
  function myFunction() {
    var d = new Date();
    var weekday = new Array(7);
    weekday[0] = "周日";
    weekday[1] = "周一";
    weekday[2] = "周二";
    weekday[3] = "周三";
    weekday[4] = "周四";
    weekday[5] = "周五";
    weekday[6] = "周六";
    var x = document.getElementById("demo");
    x.innerHTML = weekday[d.getDay()];
  }
</script>
        