function?$(id)?{ ????return?typeof??id?===?'string'???document.getElementById(id)?:?id; } window.onload?=?function?()?{ ????var?titles?=?$('main-til').getElementsByTagName('li'); ????var?divs?=?$('main-con').getElementsByTagName('div'); ????if?(titles.length?!=?divs.length) ????????return; ????for?(var?i?=?0;?i?<?titles.length;?i++)?{ ????????titles[i].id?=?i; ????????//索引 ????????titles[i].onmouseover?=?function?()?{ ????????????for?(var?j?=?0;?j?<?titles.length;?j++)?{ ????????????????titles[j].className?=?''; ????????????????divs[j].style.display?=?'none'; ????????????} ????????????this.className?=?'select'; ????????????divs[this.id].style.display?=?'block'; ????????} ????} }這段JavaScript代碼是通過var?divs?=?$('main-con').getElementsByTagName('div'); divs[this.id].style.display?=?'block';來實現(xiàn)切換的，可如果title對應的內(nèi)容欄里面又嵌套了其他幾個div呢？ 有沒有什么視頻、博客、課程來解決這個問題的？