Question

我需要计算一个房间的面积，我无法找到我的代码中的问题。更具体地说，我需要从表单中调用值，当我按下提交按钮时，我想根据我的计算打印房间区域。

getElementById似乎也不起作用，我也不知道为什么。

＆＃13;

function area() {
  var perimeter = document.getElementById("PE").value;
  var height = document.getElementById("He").value;
  var doors = document.getElementById("Nd").value;
  var doors_w_par = doors * 5.0212;
  var windows = document.getElementById("Nw").value;
  var windows_w_par = windows * 2.488;
  var closets = document.getElementById("Nc").value;
  var closets_w_par = closets * 1.37;
  var areas = (perimeter * height) - doors_w_par - windows_w_par - closets_w_par;
  return areas;
}
console.log(area());

＆＃13;

<form action="" method="POST" id="myForm">
  Perimeter:
  <input type="float" min="0" max="9999999999999" id="Pe" name="P" />
  <br/>height:
  <input type="float" min="0" max="9999999999999" id="He" name="H" />
  <br />doors:
  <input type="number" min="0" max="9999999999999" id="Nd" name="D" />
  <br />windows:
  <input type="number" min="0" max="9999999999999" id="Nw" name="W" />
  <br />closets:
  <input type="number" min="0" max="9999999999999" id="Nc" name="C" />
  <br />
  <input type="submit" value="calc" name="sub" id="subm" onClick="testResults(this.form)">
</form>
<br />

＆＃13;

Answer 1

在表单存在之前，您无法调用区域
您不需要使用提交按钮，而是使用type =“button”
PE是您的形式的Pe
我不相信表单元素可以有type =“float” - “数字”是您可能想要的或“文本”或将步骤属性添加到数字
您需要根据所做的计算来解析返回的值
使用toFixed（小数）来舍入结果

function area() {
  var perimeter = document.getElementById("Pe").value;
  perimeter = isNaN(perimeter)||perimeter==""?0:parseFloat(perimeter);
  var height = document.getElementById("He").value;
  height = isNaN(height)||height==""?0:parseFloat(height)
  var doors = document.getElementById("Nd").value;
  doors=isNaN(doors)||doors==""?0:parseInt(doors,10);
  var doors_w_par = doors * 5.0212;
  var windows = document.getElementById("Nw").value;
  windows=isNaN(windows)||windows==""?0:parseInt(windows,10);
  var windows_w_par = windows * 2.488;
  var closets = document.getElementById("Nc").value;
  closets=isNaN(closets)||closets==""?0:parseInt(closets,10);
   var closets_w_par = closets * 1.37;
  var areas = (perimeter * height) - doors_w_par - windows_w_par - closets_w_par;
  return areas.toFixed(2);
}
window.onload=function() {
  document.getElementById("subm").onclick=function() {
    console.log(area());
  }
}

<form action="" method="POST" id="myForm">
  Perimeter:
  <input type="number" step="0.01" min="0" max="9999999999999" id="Pe" name="P" />
  <br/>height:
  <input type="number" step="0.01" min="0" max="9999999999999" id="He" name="H" />
  <br />doors:
  <input type="number" min="0" max="9999999999999" id="Nd" name="D" />
  <br />windows:
  <input type="number" min="0" max="9999999999999" id="Nw" name="W" />
  <br />closets:
  <input type="number" min="0" max="9999999999999" id="Nc" name="C" />
  <br />
  <input type="button" value="calc" name="sub" id="subm" />
</form>
<br />

javascript-如何使用html表单进行区域计算

1 个答案: