运动函数
拖拽 鼠标在元素中按下,不松手 在页面中移动,让元素跟随鼠标移动 松开鼠标,拖拽停止 var oDiv = document . getElementsByTagName ( "div" ) [ 0 ] ; //1.按下 oDiv . onmousedown = function ( ev ) { var ev = window . event || ev ; //鼠标的位置-oDiv的offset var a = ev . clientX - oDiv . offsetLeft ; var b = ev . clientY - oDiv . offsetTop ; //2.拖动 document . onmousemove = function ( ev ) { var ev = window . event || ev ; var l = ev . clientX - a ; var t = ev . clientY - b ; //3.元素随鼠标移动 oDiv . style . left = l + "px" ; oDiv . style . top = t + "px" ; } //4.松手取消move document . onmouseup = function ( ) { document . onmousemove = null ; } } 拖拽的问题及解决 问题