使用 jquery 将引导程序“list-group-item”附加到“list-group”

Question

我有一个包含 textarea 和按钮表单控件的引导程序“表单组”，我想在按下按钮时将在 textarea 内写入的文本附加到列表组

这是我的页面，带有 Jquery 试用代码：

$(document).ready(function() {
  $('button:last').click(function() {
    comment = $('textarea').val();
    $('.list-group').append("<li class='list-group-item'>+comment+</li>");
  });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.3/css/bootstrap.min.css" integrity="sha384-Zug+QiDoJOrZ5t4lssLdxGhVrurbmBWopoEl+M6BdEfwnCJZtKxi1KgxUyJq13dy" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.3/js/bootstrap.min.js" integrity="sha384-a5N7Y/aK3qNeh15eJKGWxsqtnX/wWdSZSKp+81YjTmS15nvnvxKHuzaWwXHDli+4" crossorigin="anonymous"></script>
<div class="container">
  <ul class="list-group">
  </ul>
</div>
<div class="container" style="margin-top: 60px">
  <form class="well col-xs-6 col-xs-offset-3">
    <div class="form-group">
      <label id="commentTitle" for="comment">Comment:</label>
      <textarea class="form-control" rows="5" id="comment"></textarea>
    </div>
    <button class="btn btn-primary ">submit</button>
  </form>
</div>

Answer 1

你需要改变

$('.list-group').append("<li class='list-group-item'>+comment+</li>");

进入这个 $('.list-group').append("<li class='list-group-item'>"+comment+" </li>");（粗心的错误）并添加type="button"

$('.list-group').append("<li class='list-group-item'>+comment+</li>");

$(document).ready(function(){
            $('button:last').click(function() {
                comment = $('textarea').val();   
                $('.list-group').append("<li class='list-group-item'>"+comment+"</li>");
            });
        });