Be.Windows.Forms.DynamicFileByteProvider.ApplyChanges C# (CSharp) Метод

        public void ApplyChanges()
        {
            if (_readOnly)
                throw new OperationCanceledException("File is in read-only mode");

            // This method is implemented to efficiently save the changes to the same file stream opened for reading.
            // Saving to a separate file would be a much simpler implementation.

            // Firstly, extend the file length (if necessary) to ensure that there is enough disk space.
            if (_totalLength > _stream.Length)
            {
                _stream.SetLength(_totalLength);
            }

            // Secondly, shift around any file sections that have moved.
            long dataOffset = 0;
            for (DataBlock block = _dataMap.FirstBlock; block != null; block = block.NextBlock)
            {
                FileDataBlock fileBlock = block as FileDataBlock;
                if (fileBlock != null && fileBlock.FileOffset != dataOffset)
                {
                    MoveFileBlock(fileBlock, dataOffset);
                }
                dataOffset += block.Length;
            }

            // Next, write in-memory changes.
            dataOffset = 0;
            for (DataBlock block = _dataMap.FirstBlock; block != null; block = block.NextBlock)
            {
                MemoryDataBlock memoryBlock = block as MemoryDataBlock;
                if (memoryBlock != null)
                {
                    _stream.Position = dataOffset;
                    for (int memoryOffset = 0; memoryOffset < memoryBlock.Length; memoryOffset += COPY_BLOCK_SIZE)
                    {
                        _stream.Write(memoryBlock.Data, memoryOffset, (int)Math.Min(COPY_BLOCK_SIZE, memoryBlock.Length - memoryOffset));
                    }
                }
                dataOffset += block.Length;
            }

            // Finally, if the file has shortened, truncate the stream.
            _stream.SetLength(_totalLength);
            ReInitialize();
        }