/// <summary>Prefetch next level of subdirectories and files.</summary>
/// <param name="fileFilter">Search pattern or *null* for all.</param>
/// <returns>Returns *true* if more subdirectories or files available, else *false*.</returns>
protected bool PregetContents(string fileFilter)
{
bool result;
var top = stack.Peek();
if (top.Index < 0)
{
result = top.dirInfos.Length > 0;
top = stack.Head();
}
else
{
DirectoryInfo[] nextDirs = top.dirInfos[top.Index].GetDirectories(DirFilter);
if (dirComparer != null)
{
Array.Sort(nextDirs, dirComparer);
}
stack.Enqueue(new DirNode(nextDirs, -1));
result = nextDirs.Length > 0;
}
if (fileFilter != null)
{
FileInfo[] fInfos = top.dirInfos[top.Index].GetFiles(fileFilter);
if (fileComparer != null)
{
Array.Sort(fInfos, fileComparer);
}
top.FileInfos = new ReadOnlyCollection <FileInfo> (fInfos);
result = result || top.FileInfos.Count > 0;
}
return(result);
}
public T Peek()
{
if (QueuedStack.Count == 0)
{
MoveStackToQueue();
}
return(QueuedStack.Peek());
}