参考链接:https://blog.csdn.net/qq_42068550/article/details/115459826

<!doctype html>
<html>
    <head>
        <meta charset="UTF-8">
        <title>拖拽排序</title>
        <style>
      *{box-sizing: border-box;}
        ul {
           padding:0 50px;
            list-style: none;
            font-size: 0;
        }
        li {
           margin-bottom:5px;
            font-size: 16px;
           height:60px; /*ie下必须设置*/
            line-height: 60px;
            border: 1px solid #ddd;
            padding-left: 10px;
            cursor: move;
        }
      .dashed{border:3px dashed #ddd;}
       </style>
    </head>
    <body>
    <ul id="container">
      <li draggable="true">1</li>
      <li draggable="true">2</li>
      <li draggable="true">3</li>
      <li draggable="true">4</li>
      <li draggable="true">5</li>
      <li draggable="true">6</li>
      <li draggable="true">7</li>
      <li draggable="true">8</li>
      <li draggable="true">9</li>
      <li draggable="true">10</li>
      <li draggable="true">11</li>
      <li draggable="true">12</li>
      <li draggable="true">13</li>
      <li draggable="true">14</li>
      <li draggable="true">15</li>
      <li draggable="true">16</li>
      <li draggable="true">17</li>
      <li draggable="true">18</li>
      <li draggable="true">19</li>
      <li draggable="true">20</li>
    </ul>
    </body>
</html>
<script>
    var dom = document.querySelector("#container")
    var draging = null
    dom.ondragstart = function(event) {
    draging = event.target
    draging.classList.add('dashed');
    var div = document.createElement('div')
    // dataTransfer.setData把拖动对象的数据存入其中,可以用dataTransfer.getData来获取数据(ie无效)
    // dataTransfer.setDragImage可设置拖拽层(ie无效)
    // event.dataTransfer.setDragImage(div, 0, 0)
    }
    dom.ondragover = function(event) {
        // 默认无法将数据/元素放置到其他元素中。如果需要设置允许放置,必须阻止对元素的默认处理方式
        event.preventDefault()
        var target = event.target
        if (target.nodeName === "LI" && target !== draging) {
          // 获取初始位置
            var targetRect = target.getBoundingClientRect()
            var dragingRect = draging.getBoundingClientRect()
            if (target) {
                // 判断是否动画元素
                if (target.animated) {
                    return;
                }
           }
            if (_index(draging) < _index(target)) {
                // 目标比元素大,插到其后面
                // extSibling下一个兄弟元素
                target.parentNode.insertBefore(draging, target.nextSibling)
            } else {
                // 目标比元素小,插到其前面
                target.parentNode.insertBefore(draging, target)
            }
            _animate(dragingRect, draging)
            _animate(targetRect, target)
        }
  }
  dom.ondragend = function(event){
    event.target.classList.remove('dashed');
    console.log(document.getElementsByTagName('li'))
  }
  // 获取元素在父元素中的index
  function _index(el) {
      var index = 0
      if (!el || !el.parentNode) {
          return -1
      }
      // previousElementSibling:上一个兄弟元素
      while (el && (el = el.previousElementSibling)) {
          index++
      }
      return index
    }
  // 触发动画
  function _animate(prevRect, target) {
      var ms = 300
      if (ms) {
          var currentRect = target.getBoundingClientRect()
          if (prevRect.nodeType === 1) {
              prevRect = prevRect.getBoundingClientRect()
          }
          _css(target, 'transition', 'none')
          _css(target, 'transform', 'translate3d(' +
              (prevRect.left - currentRect.left) + 'px,' +
              (prevRect.top - currentRect.top) + 'px,0)'
          );

          target.offsetWidth; // 触发重绘

          _css(target, 'transition', 'all ' + ms + 'ms');
          _css(target, 'transform', 'translate3d(0,0,0)');
          // 事件到了之后把transition和transform清空
          clearTimeout(target.animated);
          target.animated = setTimeout(function() {
              _css(target, 'transition', '');
              _css(target, 'transform', '');
              target.animated = false;
          }, ms);
      }
  }
  // 给元素添加style
  function _css(el, prop, val) {
      var style = el && el.style
      if (style) {
          if (val === void 0) {
              if (document.defaultView && document.defaultView.getComputedStyle) {
                  val = document.defaultView.getComputedStyle(el, '')
              } else if (el.currentStyle) {
                  val = el.currentStyle
              }
              return prop === void 0 ? val : val[prop]
          } else {
              if (!(prop in style)) {
                  prop = '-webkit-' + prop;
              }
              style[prop] = val + (typeof val === 'string' ? '' : 'px')
          }
      }
  }
</script>

 

 posted on 2021-04-30 14:30  一个大柚子~  阅读(1148)  评论(2编辑  收藏  举报