拖拽事件demo
2022-03-11 本文已影响0人
苍老师的眼泪
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
#draggable {
width: 200px;
height: 20px;
text-align: center;
background: white;
}
.dropzone {
width: 200px;
height: 20px;
background: blueviolet;
margin-bottom: 10px;
padding: 10px;
}
</style>
</head>
<body>
<div class="dropzone">
<div id="draggable" draggable="true" ondragstart="event.dataTransfer.setData('text/plain',null)">
This div is draggable
</div>
</div>
<div class="dropzone"></div>
<div class="dropzone"></div>
<div class="dropzone"></div>
<script>
var dragged;
/* 可拖动的目标元素会触发事件 */
document.addEventListener("drag", function (event) {
}, false);
document.addEventListener("dragstart", function (event) {
// 保存拖动元素的引用(ref.)
dragged = event.target;
// 使其半透明
event.target.style.opacity = .5;
}, false);
document.addEventListener("dragend", function (event) {
// 重置透明度
event.target.style.opacity = "";
}, false);
/* 放下目标节点时触发事件 */
document.addEventListener("dragover", function (event) {
// 阻止默认动作
event.preventDefault();
}, false);
document.addEventListener("dragenter", function (event) {
// 当可拖动的元素进入可放置的目标高亮目标节点
if (event.target.className == "dropzone") {
event.target.style.background = "purple";
}
}, false);
document.addEventListener("dragleave", function (event) {
// 当拖动元素离开可放置目标节点，重置其背景
if (event.target.className == "dropzone") {
event.target.style.background = "";
}
}, false);
document.addEventListener("drop", function (event) {
// 阻止默认动作（如打开一些元素的链接）
event.preventDefault();
// 移动拖动的元素到所选择的放置目标节点
if (event.target.className == "dropzone") {
event.target.style.background = "";
dragged.parentNode.removeChild(dragged);
event.target.appendChild(dragged);
}
}, false);
</script>
</body>
</html>
https://developer.mozilla.org/zh-CN/docs/Web/API/Document/dragover_event
