javascript - Jquery如何自动为每一行分配一个从1开始的升序整数

Question

现在，当输入行号并单击按钮时，将添加相应的行数。

现在，我想为每一行分配一个从 1 开始的升序整数，大家有什么想法吗？

$('#add-row').click(function() {
  var $tbody, $row, additionalRows;
  var numNewRows = parseInt($('#insert-rows-amnt').val(), 10);

  if (isNaN(numNewRows) || numNewRows <= 0) {
    alert('Please enter number of injection');
  } else {

    $tbody = $('table tbody');
    $row = $tbody.find('tr:last');

    additionalRows = new Array(numNewRows + 0).join($row[0].outerHTML);

    $tbody.append(additionalRows);
  }
});

<input type="number" id="insert-rows-amnt" name="insert-rows-amnt" value="<?php echo $tam ?>" />
<button id="add-row" type="button">Rows no</button>
<table>
  <tbody>
    <tr>
      <td><input type="text" style="width: 100px" name="vaccineid[]"> </td>
      <td><input type="text" style="width: 160px" name="vaccinename1[]"></td>

    </tr>
</table>
<script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>

Answer 1

我更改了表主体以包含表第一列上从 1 开始的索引

$('#add-row').click(function() {
  var $tbody, $row, additionalRows;
  var numNewRows = parseInt($('#insert-rows-amnt').val(), 10);

  if (isNaN(numNewRows) || numNewRows <= 0) {
    alert('Please enter number of injection');
  } else {

    $tbody = $('table tbody');
    $row = $tbody.find('tr:last');
    var lastRowIndex=($row.index()==-1? 0:$row.index()) +1 ;
    additionalRows = new Array(numNewRows);
    for(i=0;i<numNewRows;i++)
    {
    additionalRows[i]=` <tr>
    <td>${lastRowIndex}</td>
      <td>
      <input type="text" style="width: 100px" name="vaccineid[]"></td>
      <td><input type="text" style="width:160px"name="vaccinename1[]">   				</td>
  	  </tr>`
      lastRowIndex=lastRowIndex+1;
    }
   
    $tbody.append(additionalRows.join());
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="number" id="insert-rows-amnt" name="insert-rows-amnt" value="<?php echo $tam ?>" />
<button id="add-row" type="button">Rows no</button>
<table>
  <tbody>
 
</table>