在javascript中使用复选框动态添加表列

<table id="myTable">
  <thead>
    <tr>
      <th><input type="checkbox" id="selectAll" onchange="selectAllRows()"></th>
      <th>列1</th>
      <th>列2</th>
      <th>列3</th>
    </tr>
  </thead>
  <tbody>
    <!-- 表格内容 -->
  </tbody>
</table>

function selectAllRows() {
  var checkboxes = document.querySelectorAll('tbody input[type="checkbox"]');
  var selectAllCheckbox = document.getElementById('selectAll');
  
  for (var i = 0; i < checkboxes.length; i++) {
    checkboxes[i].checked = selectAllCheckbox.checked;
  }
  
  if (selectAllCheckbox.checked) {
    addColumn();
  } else {
    removeColumn();
  }
}

function addColumn() {
  var table = document.getElementById('myTable');
  var rows = table.getElementsByTagName('tr');
  
  for (var i = 0; i < rows.length; i++) {
    var cell = document.createElement('td');
    var checkbox = document.createElement('input');
    checkbox.type = 'checkbox';
    cell.appendChild(checkbox);
    rows[i].appendChild(cell);
  }
}

function removeColumn() {
  var table = document.getElementById('myTable');
  var rows = table.getElementsByTagName('tr');
  
  for (var i = 0; i < rows.length; i++) {
    rows[i].lastElementChild.remove();
  }
}

window.onload = function() {
  selectAllRows();
};