public XlsStream(XlsHeader hdr, uint startSector)
{
m_fileStream = hdr.FileStream;
m_fat = hdr.FAT;
m_hdr = hdr;
m_startSector = startSector;
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="bytes">byte array representing current object</param>
/// <param name="header"></param>
public XlsDirectoryEntry(byte[] bytes, XlsHeader header)
{
if (bytes.Length < Length)
throw new Excel.Exceptions.BiffRecordException(Errors.ErrorDirectoryEntryArray);
m_bytes = bytes;
m_header = header;
}
public XlsBiffStream(XlsHeader hdr, uint streamStart, bool isMini, XlsRootDirectory rootDir)
: base(hdr, streamStart, isMini, rootDir)
{
bytes = base.ReadStream();
m_size = bytes.Length;
m_offset = 0;
}
/// <summary>
/// Constructs FAT table from list of sectors
/// </summary>
/// <param name="hdr">XlsHeader</param>
/// <param name="sectors">Sectors list</param>
public XlsFat(XlsHeader hdr, List<uint> sectors)
{
m_hdr = hdr;
m_sectors_for_fat = sectors.Count;
uint sector = 0, prevSector = 0;
int sectorSize = hdr.SectorSize;
byte[] buff = new byte[sectorSize];
Stream file = hdr.FileStream;
using (MemoryStream ms = new MemoryStream(sectorSize * m_sectors_for_fat))
{
lock (file)
{
for (int i = 0; i < sectors.Count; i++)
{
sector = sectors[i];
if (prevSector == 0 || (sector - prevSector) != 1)
file.Seek((sector + 1) * sectorSize, SeekOrigin.Begin);
prevSector = sector;
file.Read(buff, 0, sectorSize);
ms.Write(buff, 0, sectorSize);
}
}
ms.Seek(0, SeekOrigin.Begin);
BinaryReader rd = new BinaryReader(ms);
m_sectors = (int)ms.Length / 4;
m_fat = new List<uint>(m_sectors);
for (int i = 0; i < m_sectors; i++)
m_fat.Add(rd.ReadUInt32());
rd.Close();
ms.Close();
}
}
public XlsBiffStream(XlsHeader hdr, uint streamStart)
: base(hdr, streamStart)
{
bytes = base.ReadStream();
m_size = bytes.Length;
m_offset = 0;
}
/// <summary>
/// Creates Root Directory catalog from XlsHeader
/// </summary>
/// <param name="hdr">XlsHeader object</param>
public XlsRootDirectory(XlsHeader hdr)
{
XlsStream stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart);
byte[] array = stream.ReadStream();
byte[] tmp;
XlsDirectoryEntry entry;
List<XlsDirectoryEntry> entries = new List<XlsDirectoryEntry>();
for (int i = 0; i < array.Length; i += XlsDirectoryEntry.Length)
{
tmp = new byte[XlsDirectoryEntry.Length];
Buffer.BlockCopy(array, i, tmp, 0, tmp.Length);
entries.Add(new XlsDirectoryEntry(tmp));
}
m_entries = entries;
for (int i = 0; i < entries.Count; i++)
{
entry = entries[i];
if (m_root == null && entry.EntryType == STGTY.STGTY_ROOT)
m_root = entry;
if (entry.ChildSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.Child = entries[(int)entry.ChildSid];
if (entry.LeftSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.LeftSibling = entries[(int)entry.LeftSiblingSid];
if (entry.RightSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.RightSibling = entries[(int)entry.RightSiblingSid];
}
}
public XlsBiffStream(XlsHeader hdr, uint streamStart)
: base(hdr, streamStart)
{
bytes = base.ReadStream();
m_size = bytes.Length;
m_offset = 0;
}
public XlsStream(XlsHeader hdr, uint startSector)
{
m_fileStream = hdr.FileStream;
m_fat = hdr.FAT;
m_hdr = hdr;
m_startSector = startSector;
}
/// <summary>
/// Creates Root Directory catalog from XlsHeader
/// </summary>
/// <param name="hdr">XlsHeader object</param>
public XlsRootDirectory(XlsHeader hdr)
{
XlsStream stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart, false, null);
byte[] array = stream.ReadStream();
byte[] tmp;
XlsDirectoryEntry entry;
List<XlsDirectoryEntry> entries = new List<XlsDirectoryEntry>();
for (int i = 0; i < array.Length; i += XlsDirectoryEntry.Length)
{
tmp = new byte[XlsDirectoryEntry.Length];
Buffer.BlockCopy(array, i, tmp, 0, tmp.Length);
entries.Add(new XlsDirectoryEntry(tmp, hdr));
}
m_entries = entries;
for (int i = 0; i < entries.Count; i++)
{
entry = entries[i];
//Console.WriteLine("Directory Entry:{0} type:{1}, firstsector:{2}, streamSize:{3}, isEntryMiniStream:{4}", entry.EntryName, entry.EntryType.ToString(), entry.StreamFirstSector, entry.StreamSize, entry.IsEntryMiniStream);
if (m_root == null && entry.EntryType == STGTY.STGTY_ROOT)
m_root = entry;
if (entry.ChildSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.Child = entries[(int)entry.ChildSid];
if (entry.LeftSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.LeftSibling = entries[(int)entry.LeftSiblingSid];
if (entry.RightSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
entry.RightSibling = entries[(int)entry.RightSiblingSid];
}
stream.CalculateMiniFat(this);
}
public XlsBiffStream(XlsHeader hdr, uint streamStart, bool isMini, XlsRootDirectory rootDir)
: base(hdr, streamStart, isMini, rootDir)
{
bytes = base.ReadStream();
m_size = bytes.Length;
m_offset = 0;
}
public XlsDirectoryEntry(byte[] bytes, XlsHeader header)
{
if (bytes.Length < 0x80)
{
throw new BiffRecordException("Directory Entry error: Array is too small.");
}
this.m_bytes = bytes;
this.m_header = header;
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="bytes">byte array representing current object</param>
/// <param name="header"></param>
public XlsDirectoryEntry(byte[] bytes, XlsHeader header)
{
if (bytes.Length < Length)
{
throw new Excel.Exceptions.BiffRecordException(Errors.ErrorDirectoryEntryArray);
}
m_bytes = bytes;
m_header = header;
}
public XlsStream(XlsHeader hdr, uint startSector, bool isMini, XlsRootDirectory rootDir)
{
m_fileStream = hdr.FileStream;
m_fat = hdr.FAT;
m_hdr = hdr;
m_startSector = startSector;
m_isMini = isMini;
m_rootDir = rootDir;
CalculateMiniFat(rootDir);
}
public XlsStream(XlsHeader hdr, uint startSector, bool isMini, XlsRootDirectory rootDir)
{
m_fileStream = hdr.FileStream;
m_fat = hdr.FAT;
m_hdr = hdr;
m_startSector = startSector;
m_isMini = isMini;
m_rootDir = rootDir;
CalculateMiniFat(rootDir);
}
/// <summary>
/// Constructs FAT table from list of sectors
/// </summary>
/// <param name="hdr">XlsHeader</param>
/// <param name="sectors">Sectors list</param>
/// <param name="sizeOfSector"></param>
/// <param name="isMini"></param>
/// <param name="rootDir"></param>
public XlsFat(XlsHeader hdr, List <uint> sectors, int sizeOfSector, bool isMini, XlsRootDirectory rootDir)
{
m_isMini = isMini;
m_rootDir = rootDir;
m_hdr = hdr;
m_sectors_for_fat = sectors.Count;
sizeOfSector = hdr.SectorSize;
uint sector = 0, prevSector = 0;
//calc offset of stream . If mini stream then find mini stream container stream
//long offset = 0;
//if (rootDir != null)
// offset = isMini ? (hdr.MiniFatFirstSector + 1) * hdr.SectorSize : 0;
byte[] buff = new byte[sizeOfSector];
Stream file = hdr.FileStream;
using (MemoryStream ms = new MemoryStream(sizeOfSector * m_sectors_for_fat))
{
lock (file)
{
for (int i = 0; i < sectors.Count; i++)
{
sector = sectors[i];
if (prevSector == 0 || (sector - prevSector) != 1)
{
file.Seek((sector + 1) * sizeOfSector, SeekOrigin.Begin);
}
prevSector = sector;
file.Read(buff, 0, sizeOfSector);
ms.Write(buff, 0, sizeOfSector);
}
}
ms.Seek(0, SeekOrigin.Begin);
BinaryReader rd = new BinaryReader(ms);
m_sectors = (int)ms.Length / 4;
m_fat = new List <uint>(m_sectors);
for (int i = 0; i < m_sectors; i++)
{
m_fat.Add(rd.ReadUInt32());
}
rd.Close();
ms.Close();
}
}
public static XlsHeader ReadHeader(Stream file)
{
XlsHeader header = new XlsHeader(file);
lock (file)
{
file.Seek(0L, SeekOrigin.Begin);
file.Read(header.m_bytes, 0, 0x200);
}
if (!header.IsSignatureValid)
{
throw new HeaderException("Error: Invalid file signature.");
}
if (header.ByteOrder != 0xfffe)
{
throw new FormatException("Error: Invalid byte order specified in header.");
}
return(header);
}
/// <summary>
/// Reads Excel header from Stream
/// </summary>
/// <param name="file">Stream with Excel file</param>
/// <returns>XlsHeader representing specified file</returns>
public static XlsHeader ReadHeader(Stream file)
{
XlsHeader hdr = new XlsHeader(file);
lock (file)
{
file.Seek(0, SeekOrigin.Begin);
file.Read(hdr.m_bytes, 0, 512);
}
if (!hdr.IsSignatureValid)
{
throw new HeaderException(Errors.ErrorHeaderSignature);
}
if (hdr.ByteOrder != 0xFFFE)
{
throw new FormatException(Errors.ErrorHeaderOrder);
}
return(hdr);
}
public XlsFat(XlsHeader hdr, List <uint> sectors, int sizeOfSector, bool isMini, XlsRootDirectory rootDir)
{
this.m_isMini = isMini;
this.m_rootDir = rootDir;
this.m_hdr = hdr;
this.m_sectors_for_fat = sectors.Count;
sizeOfSector = hdr.SectorSize;
uint num = 0;
uint num2 = 0;
byte[] buffer = new byte[sizeOfSector];
Stream fileStream = hdr.FileStream;
using (MemoryStream stream2 = new MemoryStream(sizeOfSector * this.m_sectors_for_fat))
{
lock (fileStream)
{
for (int j = 0; j < sectors.Count; j++)
{
num = sectors[j];
if ((num2 == 0) || ((num - num2) != 1))
{
fileStream.Seek((num + 1) * sizeOfSector, SeekOrigin.Begin);
}
num2 = num;
fileStream.Read(buffer, 0, sizeOfSector);
stream2.Write(buffer, 0, sizeOfSector);
}
}
stream2.Seek(0L, SeekOrigin.Begin);
BinaryReader reader = new BinaryReader(stream2);
this.m_sectors = ((int)stream2.Length) / 4;
this.m_fat = new List <uint>(this.m_sectors);
for (int i = 0; i < this.m_sectors; i++)
{
this.m_fat.Add(reader.ReadUInt32());
}
reader.Close();
stream2.Close();
}
}
/// <summary>
/// Creates Root Directory catalog from XlsHeader
/// </summary>
/// <param name="hdr">XlsHeader object</param>
public XlsRootDirectory(XlsHeader hdr)
{
XlsStream stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart, false, null);
byte[] array = stream.ReadStream();
byte[] tmp;
XlsDirectoryEntry entry;
List <XlsDirectoryEntry> entries = new List <XlsDirectoryEntry>();
for (int i = 0; i < array.Length; i += XlsDirectoryEntry.Length)
{
tmp = new byte[XlsDirectoryEntry.Length];
Buffer.BlockCopy(array, i, tmp, 0, tmp.Length);
entries.Add(new XlsDirectoryEntry(tmp, hdr));
}
m_entries = entries;
for (int i = 0; i < entries.Count; i++)
{
entry = entries[i];
//Console.WriteLine("Directory Entry:{0} type:{1}, firstsector:{2}, streamSize:{3}, isEntryMiniStream:{4}", entry.EntryName, entry.EntryType.ToString(), entry.StreamFirstSector, entry.StreamSize, entry.IsEntryMiniStream);
if (m_root == null && entry.EntryType == STGTY.STGTY_ROOT)
{
m_root = entry;
}
if (entry.ChildSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.Child = entries[(int)entry.ChildSid];
}
if (entry.LeftSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.LeftSibling = entries[(int)entry.LeftSiblingSid];
}
if (entry.RightSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.RightSibling = entries[(int)entry.RightSiblingSid];
}
}
stream.CalculateMiniFat(this);
}
/// <summary>
/// Constructs FAT table from list of sectors
/// </summary>
/// <param name="hdr">XlsHeader</param>
/// <param name="sectors">Sectors list</param>
/// <param name="sizeOfSector"></param>
/// <param name="isMini"></param>
/// <param name="rootDir"></param>
public XlsFat(XlsHeader hdr, List<uint> sectors, int sizeOfSector, bool isMini, XlsRootDirectory rootDir)
{
m_isMini = isMini;
m_rootDir = rootDir;
m_hdr = hdr;
m_sectors_for_fat = sectors.Count;
sizeOfSector = hdr.SectorSize;
uint sector = 0, prevSector = 0;
//calc offset of stream . If mini stream then find mini stream container stream
//long offset = 0;
//if (rootDir != null)
// offset = isMini ? (hdr.MiniFatFirstSector + 1) * hdr.SectorSize : 0;
byte[] buff = new byte[sizeOfSector];
Stream file = hdr.FileStream;
using (MemoryStream ms = new MemoryStream(sizeOfSector * m_sectors_for_fat))
{
lock (file)
{
for (int i = 0; i < sectors.Count; i++)
{
sector = sectors[i];
if (prevSector == 0 || (sector - prevSector) != 1)
file.Seek((sector + 1) * sizeOfSector, SeekOrigin.Begin);
prevSector = sector;
file.Read(buff, 0, sizeOfSector);
ms.Write(buff, 0, sizeOfSector);
}
}
ms.Seek(0, SeekOrigin.Begin);
BinaryReader rd = new BinaryReader(ms);
m_sectors = (int)ms.Length / 4;
m_fat = new List<uint>(m_sectors);
for (int i = 0; i < m_sectors; i++)
m_fat.Add(rd.ReadUInt32());
rd.Close();
ms.Close();
}
}
private void Dispose(bool disposing)
{
// Check to see if Dispose has already been called.
if (!this.disposed)
{
if (disposing)
{
if (m_workbookData != null) m_workbookData.Dispose();
if (m_sheets != null) m_sheets.Clear();
}
m_workbookData = null;
m_sheets = null;
m_stream = null;
m_globals = null;
m_encoding = null;
m_hdr = null;
disposed = true;
}
}
/// <summary>
/// Constructs FAT table from list of sectors
/// </summary>
/// <param name="hdr">XlsHeader</param>
/// <param name="sectors">Sectors list</param>
public XlsFat(XlsHeader hdr, List <uint> sectors)
{
m_hdr = hdr;
m_sectors_for_fat = sectors.Count;
uint sector = 0, prevSector = 0;
int sectorSize = hdr.SectorSize;
byte[] buff = new byte[sectorSize];
Stream file = hdr.FileStream;
using (MemoryStream ms = new MemoryStream(sectorSize * m_sectors_for_fat))
{
lock (file)
{
for (int i = 0; i < sectors.Count; i++)
{
sector = sectors[i];
if (prevSector == 0 || (sector - prevSector) != 1)
{
file.Seek((sector + 1) * sectorSize, SeekOrigin.Begin);
}
prevSector = sector;
file.Read(buff, 0, sectorSize);
ms.Write(buff, 0, sectorSize);
}
}
ms.Seek(0, SeekOrigin.Begin);
BinaryReader rd = new BinaryReader(ms);
m_sectors = (int)ms.Length / 4;
m_fat = new List <uint>(m_sectors);
for (int i = 0; i < m_sectors; i++)
{
m_fat.Add(rd.ReadUInt32());
}
rd.Close();
ms.Close();
}
}
/// <summary>
/// Creates Root Directory catalog from XlsHeader
/// </summary>
/// <param name="hdr">XlsHeader object</param>
public XlsRootDirectory(XlsHeader hdr)
{
XlsStream stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart, false, null);
byte[] array = stream.ReadStream();
byte[] tmp;
XlsDirectoryEntry entry;
List <XlsDirectoryEntry> entries = new List <XlsDirectoryEntry>();
for (int i = 0; i < array.Length; i += XlsDirectoryEntry.Length)
{
tmp = new byte[XlsDirectoryEntry.Length];
Buffer.BlockCopy(array, i, tmp, 0, tmp.Length);
entries.Add(new XlsDirectoryEntry(tmp, hdr));
}
m_entries = entries;
for (int i = 0; i < entries.Count; i++)
{
entry = entries[i];
if (m_root == null && entry.EntryType == STGTY.STGTY_ROOT)
{
m_root = entry;
}
if (entry.ChildSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.Child = entries[(int)entry.ChildSid];
}
if (entry.LeftSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.LeftSibling = entries[(int)entry.LeftSiblingSid];
}
if (entry.RightSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
{
entry.RightSibling = entries[(int)entry.RightSiblingSid];
}
}
stream.CalculateMiniFat(this);
}
public XlsRootDirectory(XlsHeader hdr)
{
XlsStream stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart, false, null);
byte[] src = stream.ReadStream();
List <XlsDirectoryEntry> list = new List <XlsDirectoryEntry>();
for (int i = 0; i < src.Length; i += 0x80)
{
byte[] dst = new byte[0x80];
Buffer.BlockCopy(src, i, dst, 0, dst.Length);
list.Add(new XlsDirectoryEntry(dst, hdr));
}
this.m_entries = list;
for (int j = 0; j < list.Count; j++)
{
XlsDirectoryEntry entry = list[j];
if ((this.m_root == null) && (entry.EntryType == STGTY.STGTY_ROOT))
{
this.m_root = entry;
}
if (entry.ChildSid != uint.MaxValue)
{
entry.Child = list[(int)entry.ChildSid];
}
if (entry.LeftSiblingSid != uint.MaxValue)
{
entry.LeftSibling = list[(int)entry.LeftSiblingSid];
}
if (entry.RightSiblingSid != uint.MaxValue)
{
entry.RightSibling = list[(int)entry.RightSiblingSid];
}
}
stream.CalculateMiniFat(this);
}
private void fail(string message)
{
m_exceptionMessage = message;
m_isValid = false;
m_file.Close();
m_isClosed = true;
m_workbookData = null;
m_sheets = null;
m_stream = null;
m_globals = null;
m_encoding = null;
m_hdr = null;
}
private void readWorkBookGlobals()
{
//Read Header
try
{
m_hdr = XlsHeader.ReadHeader(m_file);
}
catch (Exceptions.HeaderException ex)
{
fail(ex.Message);
return;
}
catch (FormatException ex)
{
fail(ex.Message);
return;
}
XlsRootDirectory dir = new XlsRootDirectory(m_hdr);
XlsDirectoryEntry workbookEntry = dir.FindEntry(WORKBOOK) ?? dir.FindEntry(BOOK);
if (workbookEntry == null)
{ fail(Errors.ErrorStreamWorkbookNotFound); return; }
if (workbookEntry.EntryType != STGTY.STGTY_STREAM)
{ fail(Errors.ErrorWorkbookIsNotStream); return; }
m_stream = new XlsBiffStream(m_hdr, workbookEntry.StreamFirstSector);
m_globals = new XlsWorkbookGlobals();
m_stream.Seek(0, SeekOrigin.Begin);
XlsBiffRecord rec = m_stream.Read();
XlsBiffBOF bof = rec as XlsBiffBOF;
if (bof == null || bof.Type != BIFFTYPE.WorkbookGlobals)
{ fail(Errors.ErrorWorkbookGlobalsInvalidData); return; }
bool sst = false;
m_version = bof.Version;
m_sheets = new List<XlsWorksheet>();
while (null != (rec = m_stream.Read()))
{
switch (rec.ID)
{
case BIFFRECORDTYPE.INTERFACEHDR:
m_globals.InterfaceHdr = (XlsBiffInterfaceHdr)rec;
break;
case BIFFRECORDTYPE.BOUNDSHEET:
XlsBiffBoundSheet sheet = (XlsBiffBoundSheet)rec;
if (sheet.Type != XlsBiffBoundSheet.SheetType.Worksheet) break;
sheet.IsV8 = isV8();
sheet.UseEncoding = m_encoding;
m_sheets.Add(new XlsWorksheet(m_globals.Sheets.Count, sheet));
m_globals.Sheets.Add(sheet);
break;
case BIFFRECORDTYPE.MMS:
m_globals.MMS = rec;
break;
case BIFFRECORDTYPE.COUNTRY:
m_globals.Country = rec;
break;
case BIFFRECORDTYPE.CODEPAGE:
m_globals.CodePage = (XlsBiffSimpleValueRecord)rec;
try
{
m_encoding = Encoding.GetEncoding(m_globals.CodePage.Value);
}
catch (ArgumentException)
{
// Warning - Password protection
// TODO: Attach to ILog
}
break;
case BIFFRECORDTYPE.FONT:
case BIFFRECORDTYPE.FONT_V34:
m_globals.Fonts.Add(rec);
break;
case BIFFRECORDTYPE.FORMAT:
case BIFFRECORDTYPE.FORMAT_V23:
m_globals.Formats.Add(rec);
break;
case BIFFRECORDTYPE.XF:
case BIFFRECORDTYPE.XF_V4:
case BIFFRECORDTYPE.XF_V3:
case BIFFRECORDTYPE.XF_V2:
m_globals.ExtendedFormats.Add(rec);
break;
case BIFFRECORDTYPE.SST:
m_globals.SST = (XlsBiffSST)rec;
sst = true;
break;
case BIFFRECORDTYPE.CONTINUE:
if (!sst) break;
XlsBiffContinue contSST = (XlsBiffContinue)rec;
m_globals.SST.Append(contSST);
break;
case BIFFRECORDTYPE.EXTSST:
m_globals.ExtSST = rec;
sst = false;
break;
case BIFFRECORDTYPE.PROTECT:
case BIFFRECORDTYPE.PASSWORD:
case BIFFRECORDTYPE.PROT4REVPASSWORD:
//IsProtected
break;
case BIFFRECORDTYPE.EOF:
if (m_globals.SST != null)
m_globals.SST.ReadStrings();
return;
default:
continue;
}
}
}
private void ParseXlsStream(Stream fileStream)
{
using (m_file = fileStream)
{
m_hdr = XlsHeader.ReadHeader(m_file);
XlsRootDirectory dir = new XlsRootDirectory(m_hdr);
XlsDirectoryEntry workbookEntry = dir.FindEntry(WORKBOOK) ?? dir.FindEntry(BOOK);
if (workbookEntry == null)
throw new FileNotFoundException(Errors.ErrorStreamWorkbookNotFound);
if (workbookEntry.EntryType != STGTY.STGTY_STREAM)
throw new FormatException(Errors.ErrorWorkbookIsNotStream);
m_stream = new XlsBiffStream(m_hdr, workbookEntry.StreamFirstSector);
ReadWorkbookGlobals();
m_workbookData = new DataSet();
for (int i = 0; i < m_sheets.Count; i++)
{
if (ReadWorksheet(m_sheets[i]))
m_workbookData.Tables.Add(m_sheets[i].Data);
}
m_globals.SST = null;
m_globals = null;
m_sheets = null;
m_stream = null;
m_hdr = null;
GC.Collect();
GC.SuppressFinalize(this);
}
}
/// <summary>
/// Reads Excel header from Stream
/// </summary>
/// <param name="file">Stream with Excel file</param>
/// <returns>XlsHeader representing specified file</returns>
public static XlsHeader ReadHeader(Stream file)
{
XlsHeader hdr = new XlsHeader(file);
lock (file)
{
file.Seek(0, SeekOrigin.Begin);
file.Read(hdr.m_bytes, 0, 512);
}
if (!hdr.IsSignatureValid)
throw new HeaderException(Errors.ErrorHeaderSignature);
if (hdr.ByteOrder != 0xFFFE)
throw new FormatException(Errors.ErrorHeaderOrder);
return hdr;
}
