javascript - 检查是否选中了复选框

Question

这是我拥有的网站上表格的底部。在添加 TOS 协议复选框之前一切正常。现在，无论是否选中该框，它都会提醒用户他们必须选中该框。任何帮助将不胜感激。

<input type='checkbox' value='yes' name='tosagree' id='tosagree'> <p>I have read and agree to the privacy policy and terms of use found on this site.</p>
            <input type='submit' id='submit' name='submit' value='submit'><br /><br />
    </form>
</div>

<script type='text/javascript'>
function validateForm()
{
var asking=document.forms["form"]["asaskingprice"].value,
reasons=document.forms["form"]["asreasons"].value,
timelines=document.forms["form"]["astimelines"].value,
sources=document.forms["form"]["assources"].value,
tos=document.forms["form"]["tosagree"].value;
if (asking==null || asking=="")
  {
  alert("Asking price must be filled out");
  return false;
  }
if (reasons==null || reasons=="")
  {
  alert("reasons must be filled out");
  return false;
  }
if (timelines==null || timelines=="")
  {
  alert("timelines must be filled out");
  return false;
  }
if (sources==null || sources=="")
  {
  alert("sources must be filled out");
  return false;
  }
if (document.forms["form"]["tosagree"].Checked!=true)
  {
  alert("You must agree to the terms of service");
  return false;
  }
}
</script>

Answer 1

正确的属性名称是checked，不是Checked。

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/Input#attr-checked

Answer 2

你可以像这样通过它的 id 抓住那个吸盘：

var tos = document.getElementById('tosagree');

if (tos.checked) {
    //return true
}