如何避免在输入中按回车键后重新加载asp页面

<form onsubmit="return false;">
  <!-- 表单内容 -->
  <input type="text" name="inputField">
  <input type="submit" value="提交">
</form>

<script>
  document.addEventListener('keydown', function(event) {
    if (event.keyCode === 13) {
      event.preventDefault();
    }
  });
</script>

<script>
  function submitForm() {
    var formData = new FormData(document.getElementById('myForm'));
    var xhr = new XMLHttpRequest();
    xhr.open('POST', 'submit.asp', true);
    xhr.onreadystatechange = function() {
      if (xhr.readyState === 4 && xhr.status === 200) {
        // 处理服务器返回的响应数据
      }
    };
    xhr.send(formData);
  }
</script>

<form id="myForm">
  <!-- 表单内容 -->
  <input type="text" name="inputField">
  <input type="button" value="提交" onclick="submitForm()">
</form>