【JS】原生实现拖拽

时间:2023-03-09 15:02:36
【JS】原生实现拖拽
<!DOCTYPE html>
<html lang="en">
<head>    
<meta charset="UTF-8">    
<meta name="viewport" content="width=device-width, initial-scale=1.0">    
<title>Document</title>
</head>
<body>    
<!-- <img id="ball" src="https://js.cx/clipart/ball.svg" width = "100px" height = "100px" alt="">
<object data="https://js.cx/clipart/ball.svg" width="100" height="100" type="image/svg+xml" codebase="http://www.adobe.com/svg/viewer/imstall/" /> -->
<img id="ball" src = "https://www.baidu.com/img/bd_logo1.png?qua=high&where=super" alt = "logo">    
<div>helloworld</div>
<script>       
const ball=document.querySelector("#ball")       
ball.onmousedown = function(event) {       
let shiftX = event.clientX - ball.getBoundingClientRect().left;       
let shiftY = event.clientY - ball.getBoundingClientRect().top;        
ball.style.position = 'absolute';        
ball.style.zIndex = 1000;        
document.body.append(ball);        
moveAt(event.pageX, event.pageY);        
// 移动现在位于坐标 (pageX, pageY) 上的球        
// 将初始的偏移考虑在内        
function moveAt(pageX, pageY) {        
ball.style.left = pageX - shiftX + 'px';        
ball.style.top = pageY - shiftY + 'px';        
}        
function onMouseMove(event) {        
moveAt(event.pageX, event.pageY);        
}        
// 在 mousemove 事件上移动球        
document.addEventListener('mousemove', onMouseMove);        
// 放下球,并移除不需要的处理程序        
ball.onmouseup = function() {        
document.removeEventListener('mousemove', onMouseMove);        
ball.onmouseup = null;        
};        
};        
ball.ondragstart = function() {        
return false;    
};    
</script>
</body>
</html>