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<html> <head> <meta charset="utf8"> <title>js拖拽效果</title> <style type="text/css"> #div1 { width : 200px; height: 200px; position: absolute; background: #99dd33; cursor: move; } </style> </head> <body> <div id="div1"></div> </body> <script type="text/javascript"> // js代码 window.onload=function() { var disX = disY = 0; // 鼠标距离div的左距离和上距离 var div1 = document.getElementById("div1"); // 得到div1对象 // 鼠标按下div1时 div1.onmousedown = function(e) { var evnt = e || event; // 得到鼠标事件 disX = evnt.clientX - div1.offsetLeft; // 鼠标横坐标 - div1的left disY = evnt.clientY - div1.offsetTop; // 鼠标纵坐标 - div1的top // 鼠标移动时 document.onmousemove = function(e) { var evnt = e || event; var x = evnt.clientX - disX; var y = evnt.clientY - disY; var window_width = document.documentElement.clientWidth - div1.offsetWidth; var window_height = document.documentElement.clientHeight - div1.offsetHeight; x = ( x < 0 ) ? 0 : x; // 当div1到窗口最左边时 x = ( x > window_width ) ? window_width : x; // 当div1到窗口最右边时 y = ( y < 0 ) ? 0 : y; // 当div1到窗口最上边时 y = ( y > window_height ) ? window_height : y; // 当div1到窗口最下边时 div1.style.left = x + "px"; div1.style.top = y + "px"; }; // 鼠标抬起时 document.onmouseup = function() { document.onmousemove =null; document.onmouup = null; }; return false; }; }; </script> </html>
https://www.cnblogs.com/boystar/p/5231697.html
<!DOCTYPE html> <html> <head> <meta charset="utf8"> <title>js拖拽效果</title> <style type="text/css"> #div1 { width : 200px; height: 200px; position: absolute; background: #99dd33; cursor: move; } </style> </head> <body> <div id="div1"></div> </body> <script type="text/javascript"> // js代码 window.onload=function() { var disX = disY = 0; // 鼠标距离div的左距离和上距离 var div1 = document.getElementById("div1"); // 得到div1对象 // 鼠标按下div1时 div1.onmousedown = function(e) { var evnt = e || event; // 得到鼠标事件 disX = evnt.clientX - div1.offsetLeft; // 鼠标横坐标 - div1的left disY = evnt.clientY - div1.offsetTop; // 鼠标纵坐标 - div1的top // 鼠标移动时 document.onmousemove = function(e) { var evnt = e || event; var x = evnt.clientX - disX; var y = evnt.clientY - disY; var window_width = document.documentElement.clientWidth - div1.offsetWidth; var window_height = document.documentElement.clientHeight - div1.offsetHeight; x = ( x < 0 ) ? 0 : x; // 当div1到窗口最左边时 x = ( x > window_width ) ? window_width : x; // 当div1到窗口最右边时 y = ( y < 0 ) ? 0 : y; // 当div1到窗口最上边时 y = ( y > window_height ) ? window_height : y; // 当div1到窗口最下边时 div1.style.left = x + "px"; div1.style.top = y + "px"; }; // 鼠标抬起时 document.onmouseup = function() { document.onmousemove =null; document.onmouup = null; }; return false; }; }; </script> </html>