前幾天測試的時候，感覺dtree還行，也不是很慢。今天把樹分支擴大以後就懵逼了，慢的一匹。

　　仔細看了下，才發現原來畫分支的時候每次都會請求那些圖，反復請求下加載時候無形拉長了很多。沒有辦法，就只能在html中提前加載好，然後js去get圖片src。

　　html部分：

<div style = "display:none;">
      <img id = "plus" src = "../images/PPS/dtree_imgs/plus.gif"/>
      <img id = "empty" src = "../images/PPS/dtree_imgs/empty.gif"
 
/>
      <img id = "line" src = "../images/PPS/dtree_imgs/line.gif"/>
      <img id = "join" src = "../images/PPS/dtree_imgs/join.gif"/>
      <img id = "page" src = "../images/PPS/dtree_imgs/page.ico"/>
      <img id = "joinbottom" src = "../images/PPS/dtree_imgs/joinbottom.gif"/>
      <
 
img id = "plusbottom" src = "../images/PPS/dtree_imgs/plusbottom.gif"/>
      <img id = "folder-open" src = "../images/PPS/dtree_imgs/folder-open.ico"/>
      <img id = "folder-close" src = "../images/PPS/dtree_imgs/folder-close.ico"/>
      <img id = "details" src = "../images/PPS/details.ico"/>
 

 </div>

　　js部分:

this.icon = {

        root: ‘/images/PPS/dtree_imgs/base.ico‘,

        folder: $(‘#folder-close‘)[0].src,

        folderOpen: $(‘#folder-open‘)[0].src,

        node: $(‘#page‘)[0].src,

        empty: $(‘#empty‘)[0].src,

        line: $(‘#line‘)[0].src,

        join: $(‘#join‘)[0].src,

        joinBottom: $(‘#joinbottom‘)[0].src,

        plus: $(‘#plus‘)[0].src,

        plusBottom: $(‘#plusbottom‘)[0].src,

        minus: ‘/images/PPS/dtree_imgs/minus.gif‘,

        minusBottom: ‘/images/PPS/dtree_imgs/minusbottom.gif‘,

        nlPlus: ‘/images/PPS/dtree_imgs/nolines_plus.gif‘,

        nlMinus: ‘/images/PPS/dtree_imgs/nolines_minus.gif‘

    };

　　改完就快多了：

dtree加載慢的問題