Question

我想通过在Id总数中乘以常数来显示结果，我出错了？我是脚本

的新手

 <script>
       function updateOrder() {
       const X = 10;
       var Y = Document.GetElementById("small");
       var value = element.options[Y.selectedIndex].value;
       var Z = value * X;
       document.getElementById("total").value = "$" + Z.toFixed(2)}
       </script>

          <form>
          <select id="small" onchange="updateOrder();">
            <option>1</option>
            <option>2</option>
            <option>3</option>
            <option>4</option>
           </select>

        <input type="text" id="total" name="total" value=""    readonly="readonly" />
       </form> `

Answer 1

使用document.getElementById而不是Document.GetElementById和Y[Y.selectedIndex].text：

 <script>
       function updateOrder() {
       const X = 10;
       var Y = document.getElementById("small");
       var value = Y[Y.selectedIndex].text;
       var Z = value * X;
       document.getElementById("total").value = "$" + Z.toFixed(2)}
       </script>

          <form>
          <select id="small" onchange="updateOrder();">
            <option>1</option>
            <option>2</option>
            <option>3</option>
            <option>4</option>
           </select>

        <input type="text" id="total" name="total" value=""    readonly="readonly" />
       </form> `

我试图将选项值乘以常量

1 个答案: