在本教程中，我们将制作一个jQuery脚本，将常规多选框转换为动画标记输入字段。

当您在下拉框中选择选项时，这些选项将以标记的样式显示在输入字段中。要取消选择某个选项，只需单击标记中的X图标即可。

如何使用它:

1.创建倍数选择页面上的框，然后在中定义占位符文本数据占位符属性：

<select multiple data-placeholder="Select Languages">
  <option>Python</option>
  <option selected>JavaScript</option>
  <option>C/C++</option>
  <option>Java</option>
  <option>Kotlin</option>
  <option>PHP</option>
  <option>Scala</option>
  <option>Vue.js</option>
  <option>Angular</option>
  <option>React</option>
</select>

2.在文档中加载所需的jQuery库。

<script src="/path/to/cdn/jquery.min.js"></script>

3.将选择框转换为标签输入。

$(document).ready(function () {

  var select = $('select[multiple]');
  var options = select.find('option');

  var div = $('<div />').addClass('selectMultiple');
  var active = $('<div />');
  var list = $('<ul />');
  var placeholder = select.data('placeholder');

  var span = $('<span />').text(placeholder).appendTo(active);

  options.each(function () {
    var text = $(this).text();
    if ($(this).is(':selected')) {
      active.append($('<a />').html('<em>' + text + '</em><i></i>'));
      span.addClass('hide');
    } else {
      list.append($('<li />').html(text));
    }
  });

  active.append($('<div />').addClass('arrow'));
  div.append(active).append(list);

  select.wrap(div);

  $(document).on('click', '.selectMultiple ul li', function (e) {
    var select = $(this).parent().parent();
    var li = $(this);
    if (!select.hasClass('clicked')) {
      select.addClass('clicked');
      li.prev().addClass('beforeRemove');
      li.next().addClass('afterRemove');
      li.addClass('remove');
      var a = $('<a />').addClass('notShown').html('<em>' + li.text() + '</em><i></i>').hide().appendTo(select.children('div'));
      a.slideDown(400, function () {
        setTimeout(function () {
          a.addClass('shown');
          select.children('div').children('span').addClass('hide');
          select.find('option:contains(' + li.text() + ')').prop('selected', true);
        }, 500);
      });
      setTimeout(function () {
        if (li.prev().is(':last-child')) {
          li.prev().removeClass('beforeRemove');
        }
        if (li.next().is(':first-child')) {
          li.next().removeClass('afterRemove');
        }
        setTimeout(function () {
          li.prev().removeClass('beforeRemove');
          li.next().removeClass('afterRemove');
        }, 200);

        li.slideUp(400, function () {
          li.remove();
          select.removeClass('clicked');
        });
      }, 600);
    }
  });

  $(document).on('click', '.selectMultiple > div a', function (e) {
    var select = $(this).parent().parent();
    var self = $(this);
    self.removeClass().addClass('remove');
    select.addClass('open');
    setTimeout(function () {
      self.addClass('disappear');
      setTimeout(function () {
        self.animate({
          width: 0,
          height: 0,
          padding: 0,
          margin: 0
        }, 300, function () {
          var li = $('<li />').text(self.children('em').text()).addClass('notShown').appendTo(select.find('ul'));
          li.slideDown(400, function () {
            li.addClass('show');
            setTimeout(function () {
              select.find('option:contains(' + self.children('em').text() + ')').prop('selected', false);
              if (!select.find('option:selected').length) {
                select.children('div').children('span').removeClass('hide');
              }
              li.removeClass();
            }, 400);
          });
          self.remove();
        })
      }, 300);
    }, 400);
  });

  $(document).on('click', '.selectMultiple > div .arrow, .selectMultiple > div span', function (e) {
    $(this).parent().parent().toggleClass('open');
  });

});

4.标记输入所需的CSS/CS3样式。

.selectMultiple {
  width: 400px;
  position: relative;
}
.selectMultiple select {
  display: none;
}
.selectMultiple > div {
  position: relative;
  z-index: 2;
  padding: 8px 12px 2px 12px;
  border-radius: 8px;
  background: #fff;
  font-size: 14px;
  min-height: 44px;
  box-shadow: 0 4px 16px 0 rgba(22, 42, 90, 0.12);
  transition: box-shadow 0.3s ease;
}
.selectMultiple > div:hover {
  box-shadow: 0 4px 24px -1px rgba(22, 42, 90, 0.16);
}
.selectMultiple > div .arrow {
  right: 1px;
  top: 0;
  bottom: 0;
  cursor: pointer;
  width: 28px;
  position: absolute;
}
.selectMultiple > div .arrow:before, .selectMultiple > div .arrow:after {
  content: "";
  position: absolute;
  display: block;
  width: 2px;
  height: 8px;
  border-bottom: 8px solid #99A3BA;
  top: 43%;
  transition: all 0.3s ease;
}
.selectMultiple > div .arrow:before {
  right: 12px;
  transform: rotate(-130deg);
}
.selectMultiple > div .arrow:after {
  left: 9px;
  transform: rotate(130deg);
}
.selectMultiple > div span {
  color: #99A3BA;
  display: block;
  position: absolute;
  left: 12px;
  cursor: pointer;
  top: 8px;
  line-height: 28px;
  transition: all 0.3s ease;
}
.selectMultiple > div span.hide {
  opacity: 0;
  visibility: hidden;
  transform: translate(-4px, 0);
}
.selectMultiple > div a {
  position: relative;
  padding: 0 24px 6px 8px;
  line-height: 28px;
  color: #1E2330;
  display: inline-block;
  vertical-align: top;
  margin: 0 6px 0 0;
}
.selectMultiple > div a em {
  font-style: normal;
  display: block;
  white-space: nowrap;
}
.selectMultiple > div a:before {
  content: "";
  left: 0;
  top: 0;
  bottom: 6px;
  width: 100%;
  position: absolute;
  display: block;
  background: rgba(228, 236, 250, 0.7);
  z-index: -1;
  border-radius: 4px;
}
.selectMultiple > div a i {
  cursor: pointer;
  position: absolute;
  top: 0;
  right: 0;
  width: 24px;
  height: 28px;
  display: block;
}
.selectMultiple > div a i:before, .selectMultiple > div a i:after {
  content: "";
  display: block;
  width: 2px;
  height: 10px;
  position: absolute;
  left: 50%;
  top: 50%;
  background: #4D18FF;
  border-radius: 1px;
}
.selectMultiple > div a i:before {
  transform: translate(-50%, -50%) rotate(45deg);
}
.selectMultiple > div a i:after {
  transform: translate(-50%, -50%) rotate(-45deg);
}
.selectMultiple > div a.notShown {
  opacity: 0;
  transition: opacity 0.3s ease;
}
.selectMultiple > div a.notShown:before {
  width: 28px;
  transition: width 0.45s cubic-bezier(0.87, -0.41, 0.19, 1.44) 0.2s;
}
.selectMultiple > div a.notShown i {
  opacity: 0;
  transition: all 0.3s ease 0.3s;
}
.selectMultiple > div a.notShown em {
  opacity: 0;
  transform: translate(-6px, 0);
  transition: all 0.4s ease 0.3s;
}
.selectMultiple > div a.notShown.shown {
  opacity: 1;
}
.selectMultiple > div a.notShown.shown:before {
  width: 100%;
}
.selectMultiple > div a.notShown.shown i {
  opacity: 1;
}
.selectMultiple > div a.notShown.shown em {
  opacity: 1;
  transform: translate(0, 0);
}
.selectMultiple > div a.remove:before {
  width: 28px;
  transition: width 0.4s cubic-bezier(0.87, -0.41, 0.19, 1.44) 0s;
}
.selectMultiple > div a.remove i {
  opacity: 0;
  transition: all 0.3s ease 0s;
}
.selectMultiple > div a.remove em {
  opacity: 0;
  transform: translate(-12px, 0);
  transition: all 0.4s ease 0s;
}
.selectMultiple > div a.remove.disappear {
  opacity: 0;
  transition: opacity 0.5s ease 0s;
}
.selectMultiple > ul {
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 16px;
  z-index: 1;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  visibility: hidden;
  opacity: 0;
  border-radius: 8px;
  transform: translate(0, 20px) scale(0.8);
  transform-origin: 0 0;
  filter: drop-shadow(0 12px 20px rgba(22, 42, 90, 0.08));
  transition: all 0.4s ease, transform 0.4s cubic-bezier(0.87, -0.41, 0.19, 1.44), filter 0.3s ease 0.2s;
}
.selectMultiple > ul li {
  color: #1E2330;
  background: #fff;
  padding: 12px 16px;
  cursor: pointer;
  overflow: hidden;
  position: relative;
  transition: background 0.3s ease, color 0.3s ease, transform 0.3s ease 0.3s, opacity 0.5s ease 0.3s, border-radius 0.3s ease 0.3s;
}
.selectMultiple > ul li:first-child {
  border-radius: 8px 8px 0 0;
}
.selectMultiple > ul li:first-child:last-child {
  border-radius: 8px;
}
.selectMultiple > ul li:last-child {
  border-radius: 0 0 8px 8px;
}
.selectMultiple > ul li:last-child:first-child {
  border-radius: 8px;
}
.selectMultiple > ul li:hover {
  background: #4D18FF;
  color: #fff;
}
.selectMultiple > ul li:after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 6px;
  height: 6px;
  background: rgba(0, 0, 0, 0.4);
  opacity: 0;
  border-radius: 100%;
  transform: scale(1, 1) translate(-50%, -50%);
  transform-origin: 50% 50%;
}
.selectMultiple > ul li.beforeRemove {
  border-radius: 0 0 8px 8px;
}
.selectMultiple > ul li.beforeRemove:first-child {
  border-radius: 8px;
}
.selectMultiple > ul li.afterRemove {
  border-radius: 8px 8px 0 0;
}
.selectMultiple > ul li.afterRemove:last-child {
  border-radius: 8px;
}
.selectMultiple > ul li.remove {
  transform: scale(0);
  opacity: 0;
}
.selectMultiple > ul li.remove:after {
  -webkit-animation: ripple 0.4s ease-out;
          animation: ripple 0.4s ease-out;
}
.selectMultiple > ul li.notShown {
  display: none;
  transform: scale(0);
  opacity: 0;
  transition: transform 0.35s ease, opacity 0.4s ease;
}
.selectMultiple > ul li.notShown.show {
  transform: scale(1);
  opacity: 1;
}
.selectMultiple.open > div {
  box-shadow: 0 4px 20px -1px rgba(22, 42, 90, 0.12);
}
.selectMultiple.open > div .arrow:before {
  transform: rotate(-50deg);
}
.selectMultiple.open > div .arrow:after {
  transform: rotate(50deg);
}
.selectMultiple.open > ul {
  transform: translate(0, 12px) scale(1);
  opacity: 1;
  visibility: visible;
  filter: drop-shadow(0 16px 24px rgba(22, 42, 90, 0.16));
}

@-webkit-keyframes ripple {
  0% {
    transform: scale(0, 0);
    opacity: 1;
  }
  25% {
    transform: scale(30, 30);
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: scale(50, 50);
  }
}

@keyframes ripple {
  0% {
    transform: scale(0, 0);
    opacity: 1;
  }
  25% {
    transform: scale(30, 30);
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: scale(50, 50);
  }
}

预览截图

基于多选框 动画标记输入