jQuery Remove by id

以下是快速完整的解决方案。删除元素add和remove按钮的内联函数，并将事件附加到它们的id，如下所示：

var id = 0; //global id to create unique id
$(document).ready(function() {
  //attach click event to element/button with id add and remove
  $("#add,#remove").on('click', function() {
    var currentElemID = $(this).attr('id'); //get the element clicked
    if (currentElemID == "add") { //if it is add elem
      var cloneParent = $("#dataTes").clone(); //clone the dataTes element
      id=$("div[id^=dataTes]").length;//get the count of dataTes element
      //it will be always more than last count each time
      cloneParent.find('[id]').each(function() {
       //loop through each element which has id attribute in cloned set and replace them 
       //with incremented value
        var $el = $(this); //get the element
        $el.attr('id', $el.attr('id') + id);
        //ids would now be add1,add2 etc.,
      });
      cloneParent.attr('id', cloneParent.attr('id') + id);//replace cloneParent id
      cloneParent.appendTo('fieldset');//append the element to fieldset
      $("#remove").show();//show remove button only if there is more than one dataTes element
    } else {
      $("div[id^=dataTes]:last").remove();
      //just remove the last dataTes
      //[id^=dataTes]:last annotates remove last div whose id begins with dataTes
      //remember we have id like dataTes1,dataTes2 etc
      if($("div[id^=dataTes]").length==1){
         //check if only one element is present
         $("#remove").hide();//if yes hide the remove button
      }
    }
  });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<fieldset>
  <legend>Test</legend>
  <input type="submit" class="button" id="add" value="+" title="#">
  <input type="submit" class="button" id="remove" value="-" style="display:none;" title="#">
  <!--hide the remove button with display:none initially-->
  <div id="dataTes">
    <table align="center" cellpadding="3" cellspacing="0" style="border-collapse:collapse;margin-top:10px;" width="97%">
      <tr>
        <td width="100px">Test</td>
        <td width="2px">:</td>
        <td width="2px">
          <input type="text" name="usrname">
        </td>
        <td>
          <input type="submit" class="button" id="add" value="+" title="#">
          <input type="submit" class="button" id="sub" value="-" title="#">
        </td>
      </tr>
      <table align="center" cellpadding="3" cellspacing="0" style="border-collapse:collapse;margin-top:5px;margin-left:40px;" width="97%">
        <tr>
          <td width="2px"></td>
          <td width="100px">Fill</td>
          <td width="2px">:</td>
          <td>
            <input type="text" name="usrname">
          </td>
        </tr>
        <tr>
          <td width="2px"></td>
          <td width="100px">Fill</td>
          <td width="2px">:</td>
          <td>
            <input type="text" name="usrname">
          </td>
        </tr>
        <table id="dataID" align="center" cellpadding="3" cellspacing="0" style="border-collapse:collapse;margin-left:40px;" width="97%">
          <tr>
            <td width="2px"></td>
            <td width="100px">Fill</td>
            <td width="2px">:</td>
            <td>
              <input type="text" name="usrname">
            </td>
          </tr>
        </table>
      </table>
    </table>
  </div>
</fieldset>

作为注释逐行解释。如果你对此感到困惑，请告诉我。

1）重命名按钮上的重复ID（最初都是id="button"）。

<input type="submit" class="button" id = "button_duplicate" value="+" onlick="duplicate()" title = "#">
<input type="submit" class="button" id = "button_remove" value="-" onlick="remove()" title = "#">

2） 将duplicate()和remove()函数绑定到正确的按钮上。代替document.getElementById('button').onclick = duplicate;

$("#button_duplicate").click(function(){
    duplicate();
});
$("#button_remove").click(function(){
    remove();
});

3） 删除功能：

function remove(){
    if($("#dataTes" + i).length > 0){
        $("#dataTes" + i).remove();
        i--;
    }
}

i的值将在上下文中。所以你可以得到元素的id并删除它。然后递减i。试试这个：

编辑（更正代码）：

function remove(){
    var elId = "dataTes" + i;
    var element = document.getElementById(elId);
    element.parentNode.removeChild(element);
    i--;
}

同样首先，您需要更改html代码中按钮的id。

<input type="submit" class="button1" id = "add" value="-" onClick="deleteRow('#')" title = "#">

在javascript中，它应该是：

document.getElementById('button').onclick = duplicate;
document.getElementById('button1').onclick = remove;