如何通过html表单发送空值而不更改行

<form action="submit.php" method="post">
  <input type="hidden" name="hiddenField" value="">
  <!-- 其他表单字段 -->
  <input type="submit" value="提交">
</form>

<form action="submit.php" method="post" onsubmit="disableField()">
  <input type="text" name="textField" value="">
  <!-- 其他表单字段 -->
  <input type="submit" value="提交">
</form>

<script>
  function disableField() {
    document.getElementsByName("textField")[0].disabled = true;
    return true;
  }
</script>