/// <summary>
/// Reads the file header.
/// </summary>
/// <exception cref="System.IO.InvalidDataException">Stream content is in an invalid format.</exception>
private void ReadHeader()
{
_baseStream.Seek(0, SeekOrigin.Begin);
Byte[] headerBytes = new Byte[100];
_baseStream.Read(headerBytes, 0, headerBytes.Length);
// perform checks for header
if (EndianBitConverter.ToInt32(headerBytes, 0, ByteOrder.BigEndian) != 9994 || // identifier
EndianBitConverter.ToInt32(headerBytes, 24, ByteOrder.BigEndian) != _baseStream.Length / 2 || // file length
EndianBitConverter.ToInt32(headerBytes, 28, ByteOrder.LittleEndian) != 1000) // version
{
throw new InvalidDataException(MessageHeaderInvalid);
}
// shape type
_shapeType = (ShapeType)EndianBitConverter.ToInt32(headerBytes, 32, ByteOrder.LittleEndian);
// envelope
Double xMin = EndianBitConverter.ToDouble(headerBytes, 36);
Double yMin = EndianBitConverter.ToDouble(headerBytes, 44);
Double xMax = EndianBitConverter.ToDouble(headerBytes, 52);
Double yMax = EndianBitConverter.ToDouble(headerBytes, 60);
Double zMin = EndianBitConverter.ToDouble(headerBytes, 68);
Double zMax = EndianBitConverter.ToDouble(headerBytes, 76);
_envelope = new Envelope(xMin, xMax, yMin, yMax, zMin, zMax);
// load metadata for shapes
if (_fileSystem.Exists(MetadataFilePath))
{
_metadataReader = new DBaseStreamReader(OpenPath(MetadataFilePath));
}
}
/// <summary>
/// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
/// </summary>
/// <param name="disposing">A value indicating whether disposing is performed on the object.</param>
protected override void Dispose(Boolean disposing)
{
if (disposing)
{
if (_metadataReader != null)
{
_metadataReader.Dispose();
_metadataReader = null;
}
_shapeIndex = null;
}
base.Dispose(disposing);
}