javascript 中数字数组的总和

Question

在这里，我想听取用户的意见。拆分并将它们存储到数组中。然后显示数组数字的总和。

求和实验

<!-- for taking inputs -->
<input id="seriesInput" type="text" placeholder="please use space">
<!-- for submitting inputs -->
<input id="submiting" onclick="seriesFunction()" value="Submit" type="button">
<!-- for placing results -->
<div> Summation is <span id="sum"></span> </div>
<script type="text/javascript">

function seriesFunction()
{
    value = document.getElementById("seriesInput").value;
    // splitting string in an array
    value_arr = value.split(" ");
    alert(value_arr);
    // calling reduce method for summation
    var sum = value_arr.reduce(get_sum,0);
    // assigning result
    document.getElementById("sum").innerHTML =sum;
alert(sum);


    function get_sum(total, currentVal) {
total += currentVal;
return total;
}
}
</script>

Answer 1

您正在 get_sum 函数中获取字符串形式的 currentValue，请尝试将其设为整数。你可以这样做：

function get_sum(total, currentVal) {
    currentVal = parseInt(currentVal);
    total += currentVal;
    return total;
}

Answer 2

您需要将代码修改为：

function get_sum(total, currentVal) {
                total += +currentVal;
                return total;
}

注意+在currentVal前面。这会将字符串转换为数字，而不仅仅是 int。所以好处是，如果您输入三个值，如 1.1 1.2 1.3，您将得到总和为 6.6。早些时候没有这个你正在做字符串连接而不是你打算做的总和。

function seriesFunction() {
  value = document.getElementById("seriesInput").value;
  // splitting string in an array
  value_arr = value.split(" ");
  alert(value_arr);
  // calling reduce method for summation
  var sum = value_arr.reduce(get_sum, 0);
  // assigning result
  document.getElementById("sum").innerHTML = sum;
  alert(sum);


  function get_sum(total, currentVal) {
    total += +currentVal;
    return total;
  }
}

<input id="seriesInput" type="text" placeholder="please use space">
<!-- for submitting inputs -->
<input id="submiting" onclick="seriesFunction()" value="Submit" type="button">
<!-- for placing results -->
<div> Summation is <span id="sum"></span> </div>

javascript 中数字数组的总和

Summation of an array of numbers in javascript

javascript

arrays

reduce

求和实验