public bool MovePrev(AdvanceFlags flags)
{
// If before beginning or after end
if (fCurrentDirectoryList == null)
{
if (fRootDirectories == null || fRootDirectories.Length == 0)
{
return(false);
}
// if before beginning, load up the first lists
if (fCurrentFileIndex < 0)
{
return(false);
}
// Else, after end
else
{
// Load up the stack
fDirectoryStack.Clear();
fCurrentDirectoryList = new DirectoryList(fRootDirectories, fIncludeExtensions.Keys);
for (;;)
{
DirectoryList directoryList = fCurrentDirectoryList.GetSubDirectoryList();
if (directoryList.Directories.Length == 0)
{
break;
}
fDirectoryStack.Push(fCurrentDirectoryList);
fCurrentDirectoryList = directoryList;
fCurrentDirectoryList.CurrentIndex = fCurrentDirectoryList.Directories.Length - 1;
}
fCurrentFiles = fCurrentDirectoryList.GetCurrentFiles();
fCurrentFileIndex = fCurrentFiles.Length - 1;
}
}
// Else, if advance to previous folder
else if ((flags & AdvanceFlags.NextFolder) != 0)
{
fCurrentFileIndex = -1;
}
// Else, advance to previous image
else
{
--fCurrentFileIndex;
}
// Keep trying to load up an image until success or beginning is reached
for (; ;)
{
// Get current file if available
if (fCurrentFiles != null && fCurrentFiles.Length > 0 && fCurrentFileIndex >= 0)
{
fCurrent = fCurrentFiles[fCurrentFileIndex];
return(true);
}
// Move to previous folder
else
{
fCurrentFiles = null;
fCurrentFileIndex = 0;
// Pop the stack if necessary
if (fCurrentDirectoryList.CurrentIndex == 0)
{
// We're at the very beginning. Cannot go further.
if (fDirectoryStack.Count <= 0)
{
fCurrentFileIndex = -1;
fCurrentFiles = null;
fCurrentDirectoryList = null;
fCurrent = null;
return(false);
}
// Pop one directory
fCurrentDirectoryList = fDirectoryStack.Pop();
}
else
{
// Move to the previous peer folder
--fCurrentDirectoryList.CurrentIndex;
// Load up all subfolders
for (; ;)
{
DirectoryList directoryList = fCurrentDirectoryList.GetSubDirectoryList();
if (directoryList.Directories.Length == 0)
{
break;
}
fDirectoryStack.Push(fCurrentDirectoryList);
fCurrentDirectoryList = directoryList;
fCurrentDirectoryList.CurrentIndex = fCurrentDirectoryList.Directories.Length - 1;
}
}
// Load up all files
fCurrentFiles = fCurrentDirectoryList.GetCurrentFiles();
fCurrentFileIndex = fCurrentFiles.Length - 1;
}
} // End of retry loop
}
public bool MoveNext(AdvanceFlags flags)
{
// If before beginning or after end
if (fCurrentDirectoryList == null)
{
if (fRootDirectories == null || fRootDirectories.Length == 0)
{
return(false);
}
if (fCurrentFileIndex >= 0 && 0 != (flags & AdvanceFlags.Wrap))
{
Reset();
}
// if before beginning, load up the first lists
if (fCurrentFileIndex < 0)
{
fDirectoryStack.Clear();
fCurrentDirectoryList = new DirectoryList(fRootDirectories, fIncludeExtensions.Keys);
fCurrentFiles = fCurrentDirectoryList.GetCurrentFiles();
fCurrentFileIndex = 0;
}
// Else, after end
else
{
return(false);
}
}
// Else, if Advance to next folder
else if ((flags & AdvanceFlags.NextFolder) != 0)
{
fCurrentFileIndex = int.MaxValue;
}
// Else, advance image
else
{
++fCurrentFileIndex;
}
// Keep trying to load up an image until success or end is reached
for (; ;)
{
// Get next file if available
if (fCurrentFiles != null && fCurrentFileIndex < fCurrentFiles.Length)
{
fCurrent = fCurrentFiles[fCurrentFileIndex];
return(true);
}
// Advance folder
else
{
fCurrentFiles = null;
fCurrentFileIndex = 0;
// Load up the subFolders
DirectoryList directoryList = fCurrentDirectoryList.GetSubDirectoryList();
if (directoryList.Directories.Length != 0)
{
fDirectoryStack.Push(fCurrentDirectoryList);
fCurrentDirectoryList = directoryList;
}
// Else, move to the next peer folder
else
{
++fCurrentDirectoryList.CurrentIndex;
// If all folders are used up, pop levels off the stack
if (fCurrentDirectoryList.CurrentIndex >= fCurrentDirectoryList.Directories.Length)
{
fCurrentDirectoryList = null;
while (fDirectoryStack.Count > 0)
{
fCurrentDirectoryList = fDirectoryStack.Pop();
++fCurrentDirectoryList.CurrentIndex;
if (fCurrentDirectoryList.CurrentIndex < fCurrentDirectoryList.Directories.Length)
{
break;
}
fCurrentDirectoryList = null;
}
}
}
// We've popped the entire stack. At the end.
if (fCurrentDirectoryList == null)
{
if (0 == (flags & AdvanceFlags.Wrap))
{
fCurrentFileIndex = 0;
fCurrentFiles = null;
fCurrentDirectoryList = null;
fDirectoryStack.Clear();
fCurrent = null;
return(false);
}
else
{
// Wrap back to the beginning
fCurrentDirectoryList = new DirectoryList(fRootDirectories, fIncludeExtensions.Keys);
fCurrentFileIndex = 0;
}
}
// Get the files from the current folder
fCurrentFiles = fCurrentDirectoryList.GetCurrentFiles();
}
} // End of retry loop
}
