private static /*int*/ void WriteRecordToFile(BigEndianBinaryWriter shpBinaryWriter,
BigEndianBinaryWriter shxBinaryWriter, ShapeHandler handler, Geometry body, int oid)
{
if (body == null || body.IsEmpty)
{
WriteNullShapeRecord(shpBinaryWriter, shxBinaryWriter, oid);
return;
}
// Get the length of each record (in bytes)
int recordLength = handler.ComputeRequiredLengthInWords(body);
// Get the position in the stream, needed for shxBinaryWriter; since
// shpBinaryWriter.BaseStream flushes pending writes, only fetch it
// if we're going to actually touch the shx file.
long posWords = shxBinaryWriter == null ? 0 : shpBinaryWriter.BaseStream.Position / 2;
shpBinaryWriter.WriteIntBE(oid);
shpBinaryWriter.WriteIntBE(recordLength);
// update shapefile index (position in words, 1 word = 2 bytes)
if (shxBinaryWriter != null)
{
shxBinaryWriter.WriteIntBE((int)posWords);
shxBinaryWriter.WriteIntBE(recordLength);
}
handler.Write(body, shpBinaryWriter, body.Factory);
/*return recordLength;*/
}
private static /*int*/ void WriteRecordToFile(BigEndianBinaryWriter shpBinaryWriter,
BigEndianBinaryWriter shxBinaryWriter, ShapeHandler handler, IGeometry body, int oid)
{
if (body == null || body.IsEmpty)
{
WriteNullShapeRecord(shpBinaryWriter, shxBinaryWriter, oid);
return;
}
// Get the length of each record (in bytes)
var recordLength = handler.ComputeRequiredLengthInWords(body);
// Get the position in the stream
var pos = shpBinaryWriter.BaseStream.Position;
shpBinaryWriter.WriteIntBE(oid);
shpBinaryWriter.WriteIntBE(recordLength);
// update shapefile index (position in words, 1 word = 2 bytes)
var posWords = pos / 2;
shxBinaryWriter.WriteIntBE((int)posWords);
shxBinaryWriter.WriteIntBE(recordLength);
handler.Write(body, shpBinaryWriter, body.Factory);
/*return recordLength;*/
}
/// <summary>
/// Writes a shapefile to disk.
/// </summary>
/// <remarks>
/// Assumes the type given for the first geometry is the same for all subsequent geometries.
/// For example, is, if the first Geometry is a Multi-polygon/ Polygon, the subsequent geometies are
/// Muli-polygon/ polygon and not lines or points.
/// The dbase file for the corresponding shapefile contains one column called row. It contains
/// the row number.
/// </remarks>
/// <param name="filename">The filename to write to (minus the .shp extension).</param>
/// <param name="geometryCollection">The GeometryCollection to write.</param>
public void Write(IGeometryCollection geometryCollection)
{
//FileStream shpStream = new FileStream(filename + ".shp", FileMode.Create);
//FileStream shxStream = new FileStream(filename + ".shx", FileMode.Create);
shpStream = new MemoryStream();
shxStream = new MemoryStream();
BigEndianBinaryWriter shpBinaryWriter = new BigEndianBinaryWriter(shpStream);
BigEndianBinaryWriter shxBinaryWriter = new BigEndianBinaryWriter(shxStream);
// assumes
ShapeHandler handler = Shapefile.GetShapeHandler(GetShapeType(geometryCollection.Geometries[0]));
IGeometry body;
int numShapes = geometryCollection.NumGeometries;
// calc the length of the shp file, so it can put in the header.
int shpLength = 50;
for (int i = 0; i < numShapes; i++)
{
body = (IGeometry)geometryCollection.Geometries[i];
shpLength += 4; // length of header in WORDS
shpLength += handler.ComputeRequiredLengthInWords(body); // length of shape in WORDS
}
int shxLength = 50 + (4 * numShapes);
// write the .shp header
ShapefileHeader shpHeader = new ShapefileHeader();
shpHeader.FileLength = shpLength;
// get envelope in external coordinates
Envelope env = geometryCollection.EnvelopeInternal as Envelope;
Envelope bounds = ShapeHandler.GetEnvelopeExternal(geometryFactory.PrecisionModel, env);
shpHeader.Bounds = bounds;
// assumes Geometry type of the first item will the same for all other items
// in the collection.
shpHeader.ShapeType = GetShapeType(geometryCollection.Geometries[0]);
shpHeader.Write(shpBinaryWriter);
// write the .shx header
ShapefileHeader shxHeader = new ShapefileHeader();
shxHeader.FileLength = shxLength;
shxHeader.Bounds = shpHeader.Bounds;
// assumes Geometry type of the first item will the same for all other items in the collection.
shxHeader.ShapeType = GetShapeType(geometryCollection.Geometries[0]);
shxHeader.Write(shxBinaryWriter);
// write the individual records.
int _pos = 50; // header length in WORDS
for (int i = 0; i < numShapes; i++)
{
body = geometryCollection.Geometries[i];
int recordLength = handler.ComputeRequiredLengthInWords(body);
shpBinaryWriter.WriteIntBE(i + 1);
shpBinaryWriter.WriteIntBE(recordLength);
shxBinaryWriter.WriteIntBE(_pos);
shxBinaryWriter.WriteIntBE(recordLength);
_pos += 4; // length of header in WORDS
handler.Write(body, shpBinaryWriter, geometryFactory);
_pos += recordLength; // length of shape in WORDS
}
shxBinaryWriter.Flush();
//shxStream.Seek(0, SeekOrigin.Begin);
////shxBinaryWriter.Close();
shpBinaryWriter.Flush();
//shpStream.Seek(0, SeekOrigin.Begin);
//shpBinaryWriter.Close();
// WriteDummyDbf(filename + ".dbf", numShapes);
}
