前端拖拽的简单实现

鼠标按下拖动松开时鼠标的位置分析：

 

 

<!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>拖找</title>
  </head>
  <style>
    * {
      margin: 0;
      padding: 0;
    }
    html,
    body {
      height: 100%;
      width: 100%;
    }
    #box1 {
      width: 100px;
      height: 100px;
      background-color: red;
      position: absolute;
    }
  </style>
  <body>
    <div id="box1"></div>
  </body>
  <script type="text/javascript">
    window.onload = function () {
      let box1 = document.getElementById("box1");

      box1.onmousedown = function (e) {
        console.log(e.clientX, box1.offsetLeft);
        //div的偏移量.clientX - 元素.offeetLeft
        let ol = e.clientX - box1.offsetLeft;
        let ot = e.clientY - box1.offsetTop;

        // 给document绑定一个onmousemove事件
        document.onmousemove = function (event) {
          event = event || window.event;
          let left = event.clientX - ol;
          let top = event.clientY - ot;

          //修改box1的位置
          box1.style.left = left + "px";
          box1.style.top = top + "px";
        };

        document.onmouseup = function () {
          document.onmousemove = null;

          document.onmouseup = null;
        };
      };
    };
  </script>
</html>

　　

posted @ 2022-09-04 10:19  前端那点事  阅读(461)  评论(0)  编辑  收藏  举报