为什么我一直将NaN作为输出而不是正确的数据？

Question

有人可以指出我的错误。我一直以nan作为输出。

  function order() {
      var name = document.getElementById("name");
      var numOfCakeDonuts = document.getElementById("numOfCakeDonuts").valueAsNumber;
      var numOfGlazedDonuts = document.getElementById("numOfCakeDonuts").valueAsNumber;
      var time = document.getElementById("time").valueAsNumber;
      const taxrate = 0.14;
      const donutPrice = 0.50;
      var subTotal = (numOfCakeDonuts + numOfGlazedDonuts) * donutPrice;
      var tax = subTotal * taxrate;
      var total = subTotal + tax;
      document.getElementById("sub").value = subTotal.toFixed(3);
      document.getElementById("tax").value = tax.toFixed(3);
      document.getElementById("total").value = total.toFixed(3);
    }

Answer 1

误分配

您的变量numOfGlazedDonuts正在为valueAsNumber元素分配id=numOfCakeDonuts作为开头。