HeaderTreeNode.cs

using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Text;

namespace pvfLoaderXinyu
{
    struct PvfHeader//头文件内容，没什么好说的
    {
        public int sizeGUID; //Always 0x24
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x24)]
        public byte[] GUID;
        public int fileVersion;
        public int dirTreeLength;//头文件占用字节大小
        public int dirTreeChecksum;//CRC32码
        public int numFilesInDirTree;//PVF文件总数
    }
    class HeaderTreeNode
    {
        public byte[] unpackedFileByteArr;
        public int filePathLength;
        public int relativeOffset;
        public int fileLength;
        public int computedFileLength;
        public string filePathName;
        public uint fileNumber;
        public uint fileCrc32;

        public int readNodeFromBitArrStream(PvfHeader header, FileStream fs,byte[] unpackedHeaderTree, int offsite)
        {
            try
            {
                fileNumber = BitConverter.ToUInt32(unpackedHeaderTree, offsite);
                filePathLength = BitConverter.ToInt32(unpackedHeaderTree, offsite + 4);
                byte[] filePath = new byte[filePathLength];
                Array.Copy(unpackedHeaderTree, offsite + 8, filePath, 0, filePathLength);
                fileLength = BitConverter.ToInt32(unpackedHeaderTree, (offsite + filePathLength) + 8);
                fileCrc32 = BitConverter.ToUInt32(unpackedHeaderTree, (offsite + filePathLength) + 12);
                relativeOffset = BitConverter.ToInt32(unpackedHeaderTree, (offsite + filePathLength) + 0x10);
                if (fileLength > 0)
                {
                    computedFileLength = (int)((fileLength + 3L) & 4294967292L);
                    unpackedFileByteArr = new byte[computedFileLength];
                    fs.Seek(Marshal.SizeOf(typeof(PvfHeader)) + header.dirTreeLength + relativeOffset, SeekOrigin.Begin);
                    fs.Read(unpackedFileByteArr,0, computedFileLength);
                    Util.unpackHeaderTree(ref unpackedFileByteArr, computedFileLength, fileCrc32);
                    for (int i = 0; i < (computedFileLength - fileLength); i++)
                    {
                        unpackedFileByteArr[fileLength + i] = 0;
                    }
                }
                filePathName = Encoding.GetEncoding(0x3b5).GetString(filePath).TrimEnd(new char[1]);//CP949(韩语)
                return filePathLength + 20;
            }
            catch
            {
                return -1;
            }
        }
    }
}