Codeigniter Javascript动态输入只提交第一项

<form id="myForm" action="submit.php" method="post">
  <input type="text" name="input1" />
  <input type="text" name="input2" />
  <input type="text" name="input3" />
  <input type="submit" value="提交" />
</form>

<script>
  document.getElementById("myForm").addEventListener("submit", function(event) {
    event.preventDefault(); // 阻止表单默认提交行为

    var inputs = document.getElementsByTagName("input");
    var values = [];

    for (var i = 0; i < inputs.length; i++) {
      values.push(inputs[i].value);
    }

    // 只提交第一项的值
    var formData = new FormData();
    formData.append("input1", values[0]);

    // 使用Ajax发送表单数据
    var xhr = new XMLHttpRequest();
    xhr.open("POST", "submit.php", true);
    xhr.send(formData);
  });
</script>