<script src="https://www.jb51.net/js/jquery-3.5.1.js" type="text/javascript" charset="utf-8"></script> <script type="text/javascript"> $(function () { // 点击登录跳转 $("a").click(function () { $("#bg,#login").css("display","block"); }) // 定义变量 var $mX; var $mY; var $move = false; // true是可以移动登录框 // 鼠标按下事件 $("#login").mousedown(function (event) { $(this).css("opacity",0.5); // 改变透明度 $move = true; // 得到鼠标与登录框原点之间的距离 $mX = event.pageX-parseInt($(this).css("left")); $mY = event.pageY-parseInt($(this).css("top")); }) // 鼠标移动事件 $("#login").mousemove(function (event) { if($move){ // 得到登录框要移动的量 $(this).css("left",(event.pageX-$mX)+"px") $(this).css("top",(event.pageY-$mY)+"px") } }).mouseup(function () { // 鼠标弹起事件 $move = false; $(this).css("opacity",1); }) }) </script>
2.css
<style type="text/css"> *{ margin: 0; padding: 0; } h3{ display: block; width: 300px; height: 50px; text-align: center; line-height: 50px; background-color: #0076A9; } #login{ width: 300px; height: 200px; margin: 0 auto; position: absolute; top: 250px; left: 500px; border: 1px solid #000000; background-color: #FFFFFF; cursor: move; display: none; } table{ position: absolute; top: 50px; left: 0; width: 100%; height: 150px; text-align:center; } tr,td{ border: none; } tr{ height: 50px; } td{ padding: 0 5px 0 5px; } #bg{ width: 100%; height: 100%; background-color:#999999; position: absolute; top: 0; left: 0; display: none; } body{ width: 100%; height: 600px; } </style>
3.HTML
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>登录界面</title> </head> <body> <a href="javascript:;" >登录</a> <div></div> <form action="javascript:;" method=""> <h3>欢迎登录！</h3> <table cellspacing="0" cellpadding="0"> <tr> <td>用户名：</td> <td><input type="text"/></td> </tr> <tr> <td>密码：</td> <td><input type="password"/></td> </tr> <tr> <td colspan="2"> <input type="button" value="提交"/>       <input type="button" value="重置"/> </td> </tr> </table> </form> </body> </html>