javascript - 表单验证 JavaScript

Question

我正在使用一些 JavaScript 来验证表单。它在 Firefox、IE10 和 Chrome 中运行良好。有没有办法让下面的代码在 Safari 和 IE9 中工作？单击捐赠按钮时，应该要求输入学生的姓名。但在 Safari 和 IE9 中，强制字段不会被识别，它只会带你直接访问 paypal。

 <script>
function validateForm()
{
var x=document.forms["myForm"]["os0"].value;
if (x==null || x=="")
  {
  alert("Please Enter the Child Your Sponsoring and Click Donate");
  return false;
  }
}
</script>
<form name="myForm" action="https://www.paypal.com/cgi-bin/webscr" onsubmit="return  validateForm()" method="post">

<input type="hidden" name="on0" value="Child Sponsored Name" />Please enter the student's First and Last Name Your Sponsoring and click Donate

<input type="text" maxlength="200" name="os0" required/><input type="hidden" name="cmd" value="_donations" />

<input type="hidden" name="business" value="<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="c5a0a8a4aca985b2a0a7b6acb1a0eba6aaa8" rel="noreferrer noopener nofollow">[email protected]</a>" /><input type="hidden" name="lc" value="US" />

<input type="hidden" name="item_name" value="5k Run Fundraiser" />

<input type="hidden" name="no_note" value="0" />

<input type="hidden" name="cn" value="ADD DONOR NAME" />

<input type="hidden" name="no_shipping" value="2" />

<input type="hidden" name="currency_code" value="USD" />

<input type="hidden" name="bn" value="PP-DonationsBF:btn_donateCC_LG.gif:NonHosted" />

<input type="image" alt="PayPal - The safer, easier way to pay online!" name="submit" src="https://www.paypalobjects.com/en_US/i/btn/btn_donateCC_LG.gif" />

<img alt="" src="https://www.paypalobjects.com/en_US/i/scr/pixel.gif" width="1" height="1" border="0" />

</form>

Answer 1

试试这个(不知道为什么你需要表单元素):

var x = document.getElementsByName("os0")[0].value;