void FillDirTree()
 {
     rootEntry_ = new DirEntry {
         directory_ = RootPath, shortName_ = new System.IO.DirectoryInfo(RootPath).Name
     };
     rootEntry_.PopulateChildren();
 }
 internal void PopulateChildren()
 {
     string[] dirs = System.IO.Directory.GetDirectories(directory_);
     if (dirs != null)
     {
         for (int i = 0; i < dirs.Length; ++i)
         {
             DirEntry ent = new DirEntry {
                 directory_ = dirs[i], shortName_ = new System.IO.DirectoryInfo(dirs[i]).Name
             };
             ent.PopulateChildren();
             children_.Add(ent);
         }
     }
 }