在可编辑的HTML表中添加新行，并将其保存

<table id="myTable">
  <thead>
    <tr>
      <th>姓名</th>
      <th>年龄</th>
      <th>性别</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td contenteditable="true"></td>
      <td contenteditable="true"></td>
      <td contenteditable="true"></td>
    </tr>
  </tbody>
</table>

<button onclick="addRow()">添加行</button>

function addRow() {
  var table = document.getElementById("myTable");
  var newRow = table.insertRow(table.rows.length);
  
  var cell1 = newRow.insertCell(0);
  var cell2 = newRow.insertCell(1);
  var cell3 = newRow.insertCell(2);
  
  cell1.contentEditable = true;
  cell2.contentEditable = true;
  cell3.contentEditable = true;
}