private void ReadHeader()
{
byte[] buffer = this.reader.ReadBytes(Marshal.SizeOf(typeof(DBFHeader)));
// Marshall the header into a DBFHeader structure
GCHandle handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
this.header = (DBFHeader)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(DBFHeader));
handle.Free();
this.fields = new List <DBFFieldDescriptor>();
while (this.reader.PeekChar() != 13)
{
buffer = this.reader.ReadBytes(Marshal.SizeOf(typeof(DBFFieldDescriptor)));
handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
var fieldDescriptor = (DBFFieldDescriptor)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(DBFFieldDescriptor));
if ((fieldDescriptor.Flags & DBFFieldFlags.System) != DBFFieldFlags.System)
{
this.fields.Add(fieldDescriptor);
}
handle.Free();
}
byte headerTerminator = this.reader.ReadByte();
byte[] backlink = this.reader.ReadBytes(263);
}
public DBFReader(Stream anIn)
{
try
{
_dataInputStream = new BinaryReader(anIn);
isClosed = false;
_header = new DBFHeader();
_header.Read(_dataInputStream);
/* it might be required to leap to the start of records at times */
int t_dataStartIndex = _header.HeaderLength
- (32 + (32 * _header.FieldArray.Length))
- 1;
if (t_dataStartIndex > 0)
{
_dataInputStream.ReadBytes((t_dataStartIndex));
}
}
catch (IOException e)
{
throw new DBFException("Failed To Read DBF", e);
}
}
public DBFReader(string anIn)
{
try
{
_dataInputStream = new BinaryReader(
File.Open(anIn,
FileMode.Open,
FileAccess.Read,
FileShare.Read)
);
var dbtPath = Path.ChangeExtension(anIn, "dbt");
if (File.Exists(dbtPath))
{
_dataMemoLoc = dbtPath;
}
isClosed = false;
_header = new DBFHeader();
_header.Read(_dataInputStream);
/* it might be required to leap to the start of records at times */
int t_dataStartIndex = _header.HeaderLength
- (32 + (32 * _header.FieldArray.Length))
- 1;
if (t_dataStartIndex > 0)
{
_dataInputStream.ReadBytes((t_dataStartIndex));
}
}
catch (IOException ex)
{
throw new DBFException("Failed To Read DBF", ex);
}
}
public DBFWriter(Stream dbfFile)
{
raf = dbfFile;
/* before proceeding check whether the passed in File object
is an empty/non-existent file or not.
*/
if (raf.Length == 0)
{
header = new DBFHeader();
return;
}
header = new DBFHeader();
header.Read(new BinaryReader(raf));
/* position file pointer at the end of the raf */
raf.Seek(-1, SeekOrigin.End);
/* to ignore the END_OF_DATA byte at EoF */
recordCount = header.NumberOfRecords;
}
/// Creates a DBFWriter which can append to records to an existing DBF file.
/// @param dbfFile. The file passed in shouls be a valid DBF file.
/// @exception Throws DBFException if the passed in file does exist but not a valid DBF file, or if an IO error occurs.
public DBFWriter(String dbfFile)
{
try
{
raf =
File.Open(dbfFile,
FileMode.OpenOrCreate,
FileAccess.ReadWrite);
_dataMemoLoc = Path.ChangeExtension(dbfFile, "dbt");
/* before proceeding check whether the passed in File object
is an empty/non-existent file or not.
*/
if (raf.Length == 0)
{
header = new DBFHeader();
return;
}
header = new DBFHeader();
header.Read(new BinaryReader(raf));
/* position file pointer at the end of the raf */
raf.Seek(-1, SeekOrigin.End);
/* to ignore the END_OF_DATA byte at EoF */
}
catch (FileNotFoundException e)
{
throw new DBFException("Specified file is not found. ", e);
}
catch (IOException e)
{
throw new DBFException(" while reading header", e);
}
recordCount = header.NumberOfRecords;
}
/// Creates an empty Object.
public DBFWriter()
{
header = new DBFHeader();
}
