Clone form, add new each one

问题

I need to add one by one form when I click the button, but in the second click the function appends more than one form.

What am I doing wrong in my script?

Thanks

$('.add-more-btn').click(function() {
  var clone = $('.form-main').clone('.form-block');
   var   block = $('.form-block')
  $(block).append(clone);
});

<link href="https://code.jquery.com/ui/1.12.1/themes/smoothness/jquery-ui.css" rel="stylesheet" type="text/css" />
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
  <script src="https://code.jquery.com/jquery-3.1.0.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
  <title>Clone forms</title>
</head>
<body>
<div class="container">
  <div class="row">
  <div class="col-xs-12">
    <form class="form-main">
      <div class="form-block">
        <div class="form-group">
          Name
        <input type="text" name="name[]" class="form-control">
        </div>
        <div class="form-group">
          Email
        <input type="text" name="email[]" class="form-control">
        </div>
        <hr>
      </div>
    </form>
    <a class="btn btn-primary add-more-btn">Add one</a>
  </div>
</div>
</div>

回答1:

You want to duplicate the .form-block and append it to the <form>...
So identify the elements correctly first... The form and the element to be cloned.

Then, .clone() from a stored "template" on click.

Notice that you have to clone for the "template"... And again on click!

var template = $(".form-block").clone();
var form = $(".form-main");

$('.add-more-btn').on('click',function() {
   var newFormBlock = template.clone(); // Clone again here, to be able to append more than once.
   form.append(newFormBlock);
});

<link href="https://code.jquery.com/ui/1.12.1/themes/smoothness/jquery-ui.css" rel="stylesheet" type="text/css" />
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
  <script src="https://code.jquery.com/jquery-3.1.0.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
  <title>Clone forms</title>
</head>
<body>
<div class="container">
  <div class="row">
  <div class="col-xs-12">
    <form class="form-main">
      <div class="form-block">
        <div class="form-group">
          Name
        <input type="text" name="name[]" class="form-control">
        </div>
        <div class="form-group">
          Email
        <input type="text" name="email[]" class="form-control">
        </div>
        <hr>
      </div>
    </form>
    <a class="btn btn-primary add-more-btn">Add one</a>
  </div>
</div>
</div>

回答2:

Because using the clone method on a css class every div container with the css class .form-block is cloned. As you add another block with the css class .form-block you 've got two blocks with the same class name. On the next click you clone two items and so on.

Why not using the HTML5 template tag. Using this native type of templating you can archive several advantages. Your form will be faster, because you don 't need to load the jQuery library. With a few lines of native JavaScript you can archive, what you want. Have a look at the following example.

<form id="my-form" action="" method="post">

</form>
<button id="add-button">Add</button>
<template id="my-template">
    <div>
        <label>
            <span>Name</span>
            <input type="text" name="name[]" placeholder="your name">
        </label>
    </div>
</template>

This is an html example so far. You can add your own input elements and styles here. This piece of code is just for example purposes.

Now it 's time for some native JavaScript.

<script>
    document.getElementById('add-button').addEventListener('click', function(event) {
        var form = document.getElementById('my-form'),
            template = document.getElementById('my-template'),
            clone = document.importNode(template.content, true);

        form.appendChild(clone);
    }, false);

    // to add the first input element automatically
    var event = new Event('click');
    document.getElementById('add-button').dispatchEvent(event);
</script>

This works on every modern browser. For more detals about the html5 template tag and its functionality have a look at the MDN Web Docs. Also have a look at caniuse.com to see the browser support. As you can see, Microsofts Internet Explorer 11 does not support the template tag and its functionality. For that there are some astounding polyfills like the Web Components small template polyfill you could use, when IE11 support is in need.

回答3:

Another solution with html which copy the first set of element.

var clone = $('.form-main').html();
$('.add-more-btn').click(function() {
  $('.form-main').append(clone);
});

<link href="https://code.jquery.com/ui/1.12.1/themes/smoothness/jquery-ui.css" rel="stylesheet" type="text/css" />
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
  <script src="https://code.jquery.com/jquery-3.1.0.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
  <title>Clone forms</title>
</head>
<body>
<div class="container">
  <div class="row">
  <div class="col-xs-12">
    <form class="form-main">
      <div class="form-block">
        <div class="form-group">
          Name
        <input type="text" name="name[]" class="form-control">
        </div>
        <div class="form-group">
          Email
        <input type="text" name="email[]" class="form-control">
        </div>
        <hr>
      </div>
    </form>
    <a class="btn btn-primary add-more-btn">Add one</a>
  </div>
</div>
</div>

回答4:

Do not clone on button click. It is cloning what is in the form at the time of click which is increasing with every click. Instead, clone the form on load and store it in a variable. Then use it as many times.

var clone = $('.form-block').clone();
$('.add-more-btn').click(function() {
  $('.form-main').append(clone);
});

And note that .clone() does not take the parameter you were passing.

来源：https://stackoverflow.com/questions/55268627/clone-form-add-new-each-one

标签

javascript

jquery

forms

clone