private void WriteShpHeader(BigEndianBinaryWriter shpBinaryWriter, int shpLength, Envelope bounds)
{
var shpHeader = new ShapefileHeader
{
FileLength = shpLength,
Bounds = NotNull(bounds),
ShapeType = _geometryType
};
// assumes Geometry type of the first item will the same for all other items
// in the collection.
shpHeader.Write(shpBinaryWriter);
}
private void WriteShxHeader(BigEndianBinaryWriter shxBinaryWriter, int shxLength, Envelope bounds)
{
// write the .shx header
var shxHeader = new ShapefileHeader
{
FileLength = shxLength,
Bounds = NotNull(bounds),
ShapeType = _geometryType
};
// assumes Geometry type of the first item will the same for all other items in the collection.
if (shxBinaryWriter != null)
{
shxHeader.Write(shxBinaryWriter);
}
}
private static void WriteNullShapeRecord(BigEndianBinaryWriter shpBinaryWriter,
BigEndianBinaryWriter shxBinaryWriter, int oid)
{
const int recordLength = 12;
// Update shapefile index (position in words, 1 word = 2 bytes)
var posWords = shpBinaryWriter.BaseStream.Position / 2;
if (shxBinaryWriter != null)
{
shxBinaryWriter.WriteIntBE((int)posWords);
shxBinaryWriter.WriteIntBE(recordLength);
}
// Add shape
shpBinaryWriter.WriteIntBE(oid);
shpBinaryWriter.WriteIntBE(recordLength);
shpBinaryWriter.Write((int)ShapeGeometryType.NullShape);
}
/// <summary>
/// Writes a shapefile header to the given stream;
/// </summary>
/// <param name="file">The binary writer to use.</param>
public void Write(BigEndianBinaryWriter file)
{
if (file == null)
{
throw new ArgumentNullException("file");
}
if (_fileLength == -1)
{
throw new InvalidOperationException("The header properties need to be set before writing the header record.");
}
var pos = 0;
file.WriteIntBE(_fileCode);
pos += 4;
for (var i = 0; i < 5; i++)
{
file.WriteIntBE(0);//Skip unused part of header
pos += 4;
}
file.WriteIntBE(_fileLength);
pos += 4;
file.Write(_version);
pos += 4;
var format = EnumUtility.Format(typeof(ShapeGeometryType), _shapeType, "d");
file.Write(int.Parse(format));
pos += 4;
// Write the bounding box
file.Write(_bounds.MinX);
file.Write(_bounds.MinY);
file.Write(_bounds.MaxX);
file.Write(_bounds.MaxY);
pos += 8 * 4;
// Skip remaining unused bytes
for (int i = 0; i < 4; i++)
{
file.Write(0.0); // Skip unused part of header
pos += 8;
}
}
public ShapefileWriter(IGeometryFactory geometryFactory, IStreamProviderRegistry streamProviderRegistry,
ShapeGeometryType geomType)
: this(geometryFactory)
{
_shpStream = streamProviderRegistry[StreamTypes.Shape].OpenWrite(true);
_shxStream = streamProviderRegistry[StreamTypes.Index].OpenWrite(true);
_geometryType = geomType;
_shpBinaryWriter = new BigEndianBinaryWriter(_shpStream);
WriteShpHeader(_shpBinaryWriter, 0, new Envelope(0, 0, 0, 0));
if (_shxStream != null)
{
_shxBinaryWriter = new BigEndianBinaryWriter(_shxStream);
WriteShxHeader(_shxBinaryWriter, 0, new Envelope(0, 0, 0, 0));
}
_shapeHandler = Shapefile.GetShapeHandler(geomType);
}
