window.onload=function(){ var aLi =document.getElementById("li1"); aLi.onmousemove=function(){ ? // ?必須是aLi,不能是this???? startMove(aLi,'width',200,function(){ startMove(aLi,'height',200,function(){ startMove(aLi,'opacity',100); }); }); ｝ }在startMove（）中為什么aLi都寫成this不行呢，控制臺顯示Uncaught TypeError: Failed to execute 'getComputedStyle' on 'Window': parameter 1 is not of type 'Element'.191move.js:9 Uncaught TypeError: Failed to execute 'getComputedStyle' on 'Window': parameter 1 is not of type 'Element'.這錯誤。全部改成aLi卻正常能夠運行。