用js如何遍历指定的文件夹,使用模拟多线程?

Question

function showFolders(obj, click)
{//处理并显示文件夹中的子文件夹
     if (obj.tagName != "LI")
     {
       return 0;
     }
     
     if (click)
     {//点击,选择      
         if (obj.disabled == false)
         {                
           if (typeof(selectedPath) == "object")
           {
              selectedPath.removeAttribute("id");
           }
           
           obj.id = "selectedPath";
           folderSpan.path = obj.path;
         }
     }else if (obj.type == "disc")
      {
          if ( (obj.nextSibling == null) || (obj.nextSibling.tagName == "LI"))
          {//展开
          
             var drvs = new Enumerator(fso.getfolder(obj.path).SubFolders);
             var drvsText = '<dir>';
             var drv;
             var liType;
             var folderL;
             
                 for (; !drvs.atEnd(); drvs.moveNext())
                 {
                     drv = drvs.item();
                     liType = "circle";
                     
                     try
                     {
                       folderL = fso.getfolder(drv).SubFolders.count;
                     }catch(e)
                      {
                        folderL = 0;
                      }
                      
                     if (folderL)
                     {//有文件夹
                       liType = "disc";
                     }
               
                     drvsText += '<li type="' + liType + '" path="' + drv.path + '">' + drv.name;
                 }
             drvsText += '</dir>';
   
             obj.insertAdjacentHTML("afterEnd",drvsText);
         }else
          {
             obj.nextSibling.outerHTML = "";
          }
      }
}function showDrivers(functionH)
{//处理并显示电脑中硬盘
    folderSpan.evalText = functionH;
    folderSpan.style.display = "";
    
    var drvs = new Enumerator(fso.Drives);
    var drvsText = '<input type=button value="取消" onclick="folderSpan.style.display =\'none\'; folderSpan.evalText = \'\'; folderSpan.path = \'\';">';
    drvsText += '<input type=button value="确定" onclick="folderSpan.style.display =\'none\'; eval(folderSpan.evalText);">';
    drvsText += '<dir id=myDrivers ondblclick="showFolders(event.srcElement, 0)" onclick="showFolders(event.srcElement, 1)" style="width:255px; height:270px; overflow:auto;">';
    var drv;
    var liType;
    var disabled;
    var typeText;
    var folderL;
    
         for (; !drvs.atEnd(); drvs.moveNext())
         {
            drv = drvs.item();
            liType = "circle";
            disabled = " disabled";
            typeText = "本地磁盘";            if (drv.IsReady)
            {//可用
               disabled = "";
               
                     
               try
               {
                    folderL = fso.getfolder(drv.rootfolder).SubFolders.count;
               }catch(e)
                {
                        folderL = 0;
                }
                
               if (folderL)
               {//有文件夹
                 liType = "disc";
               }
               
               drvsText += '<li type="' + liType + '" path="' + drv.rootfolder + '"' + disabled + '>' + typeText + drv.VolumeName + "(" + drv.DriveLetter + ")";         
            }else
             {
                   switch (drv.DriveType)
                  {
                     case 0: typeText = "未知设置"; break;
                     case 1: typeText = "移动磁盘"; break;
                     case 2: typeText = "软盘"; break;
                     case 3: typeText = "网络磁盘"; break;
                     case 4: typeText = "光驱"; break;
                     case 5: typeText = "闪存磁盘"; break;
                  }                   drvsText += '<li type="' + liType + '" path="' + drv + '"' + disabled + '>' + typeText + "(" + drv.DriveLetter + ")";
             }
         }
   
   drvsText += '</dir>';
   
   folderSpan.innerHTML = drvsText;
}
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