コード例 #1
0
        /// <summary>
        /// A Shapefile MultiPoint Shape
        /// </summary>
        /// <param name="recordNumber">The record number in the Shapefile</param>
        /// <param name="metadata">Metadata about the shape</param>
        /// <param name="dataRecord">IDataRecord associated with the metadata</param>
        /// <param name="shapeData">The shape record as a byte array</param>
        /// <exception cref="ArgumentNullException">Thrown if shapeData is null</exception>
        /// <exception cref="InvalidOperationException">Thrown if an error occurs parsing shapeData</exception>
        protected internal ShapeMultiPoint(int recordNumber, ArrayList metadata, IDataRecord dataRecord, byte[] shapeData)
            : base(ShapeType.MultiPoint, recordNumber, metadata, dataRecord)
        {
            // metadata is validated by the base class
            if (shapeData == null)
            {
                throw new ArgumentNullException("shapeData");
            }

            // Note, shapeData includes an 8 byte header so positions below are +8
            // Position     Field       Value       Type        Number      Order
            // Byte 0       Shape Type  8           Integer     1           Little
            // Byte 4       Box         Box         Double      4           Little
            // Byte 36      NumPoints   Num Points  Integer     1           Little
            // Byte 40      Points      Points      Point       NumPoints   Little

            // validation step 1 - must have at least 8 + 4 + (4*8) + 4 bytes = 48
            if (shapeData.Length < 48)
            {
                throw new InvalidOperationException("Invalid shape data");
            }

            // extract bounding box and points
            _boundingBox = ParseBoundingBox(shapeData, 12, ProvidedOrder.Little);
            int numPoints = EndianBitConverter.ToInt32(shapeData, 44, ProvidedOrder.Little);

            // validation step 2 - we're expecting 16 * numPoints + 48 bytes total
            if (shapeData.Length != 48 + (16 * numPoints))
            {
                throw new InvalidOperationException("Invalid shape data");
            }

            // now extract the points
            _points = new PointD[numPoints];
            for (int pointNum = 0; pointNum < numPoints; pointNum++)
            {
                _points[pointNum] = new PointD(EndianBitConverter.ToDouble(shapeData, 48 + (16 * pointNum), ProvidedOrder.Little),
                                               EndianBitConverter.ToDouble(shapeData, 56 + (16 * pointNum), ProvidedOrder.Little));
            }
        }
コード例 #2
0
        /// <summary>
        /// Function is basically the same as Shape.ParsePolyLineOrPolygon, it is just
        /// extended to handle the M extreme values
        /// </summary>
        /// <param name="shapeData">The shape record as a byte array</param>
        /// <param name="boundingBox">Returns the bounding box</param>
        /// <param name="parts">Returns the list of parts</param>
        private void ParsePolyLineM(byte[] shapeData, out RectangleD boundingBox, out List <PointD[]> parts)
        {
            boundingBox = new RectangleD();
            parts       = null;

            // metadata is validated by the base class
            if (shapeData == null)
            {
                throw new ArgumentNullException("shapeData");
            }

            // Note, shapeData includes an 8 byte header so positions below are +8
            // Position     Field       Value       Type        Number      Order
            // Byte 0       Shape Type  23          Integer     1           Little
            // Byte 4       Box         Box         Double      4           Little
            // Byte 36      NumParts    NumParts    Integer     1           Little
            // Byte 40      NumPoints   NumPoints   Integer     1           Little
            // Byte 44      Parts       Parts       Integer     NumParts    Little
            // Byte X       Points      Points      Point       NumPoints   Little
            // Byte Y*      Mmin        Mmin        Double      1           Little
            // Byte Y + 8*  Mmax        Mmax        Double      1           Little
            // Byte Y + 16* Marray      Marray      Double      NumPoints   Little

            //
            // *optional

            // validation step 1 - must have at least 8 + 4 + (4*8) + 4 + 4 bytes = 52
            if (shapeData.Length < 44)
            {
                throw new InvalidOperationException("Invalid shape data");
            }

            // extract bounding box, number of parts and number of points
            boundingBox = ParseBoundingBox(shapeData, 12, ProvidedOrder.Little);
            int numParts  = EndianBitConverter.ToInt32(shapeData, 44, ProvidedOrder.Little);
            int numPoints = EndianBitConverter.ToInt32(shapeData, 48, ProvidedOrder.Little);

            // validation step 2 - we're expecting 4 * numParts + (16 + 8 * numPoints for m extremes and values) + 16 * numPoints + 52 bytes total
            if (shapeData.Length != 52 + (4 * numParts) + 16 + 8 * numPoints + (16 * numPoints))
            {
                throw new InvalidOperationException("Invalid shape data");
            }

            // now extract the parts
            int partsOffset = 52 + (4 * numParts);

            parts = new List <PointD[]>(numParts);
            for (int part = 0; part < numParts; part++)
            {
                // this is the index of the start of the part in the points array
                int startPart = (EndianBitConverter.ToInt32(shapeData, 52 + (4 * part), ProvidedOrder.Little) * 16) + partsOffset;

                int numBytes;
                if (part == numParts - 1)
                {
                    // it's the last part so we go to the end of the point array
                    numBytes = shapeData.Length - startPart;

                    // remove bytes for M extreme block
                    numBytes -= numPoints * 8 + 16;
                }
                else
                {
                    // we need to get the next part
                    int nextPart = (EndianBitConverter.ToInt32(shapeData, 52 + (4 * (part + 1)), ProvidedOrder.Little) * 16) + partsOffset;
                    numBytes = nextPart - startPart;
                }

                // the number of 16-byte points to read for this segment
                int numPointsInPart = (numBytes) / 16;

                PointD[] points = new PointD[numPointsInPart];
                for (int point = 0; point < numPointsInPart; point++)
                {
                    points[point] = new PointD(EndianBitConverter.ToDouble(shapeData, startPart + (16 * point), ProvidedOrder.Little),
                                               EndianBitConverter.ToDouble(shapeData, startPart + 8 + (16 * point), ProvidedOrder.Little));
                }

                parts.Add(points);
            }

            // parse M information
            Mmin = EndianBitConverter.ToDouble(shapeData, 52 + (4 * numParts) + (16 * numPoints), ProvidedOrder.Little);
            Mmax = EndianBitConverter.ToDouble(shapeData, 52 + 8 + (4 * numParts) + (16 * numPoints), ProvidedOrder.Little);

            M.Clear();
            for (int i = 0; i < numPoints; i++)
            {
                double _m = EndianBitConverter.ToDouble(shapeData, 52 + 16 + (4 * numParts) + (16 * numPoints) + i * 8, ProvidedOrder.Little);
                M.Add(_m);
            }
        }
コード例 #3
0
        /// <summary>
        /// Create a new Shapefile object and open a Shapefile. Note that three files are required -
        /// the main file (.shp), the index file (.shx) and the dBASE table (.dbf). The three files
        /// must all have the same filename (i.e. shapes.shp, shapes.shx and shapes.dbf). Set path
        /// to any one of these three files to open the Shapefile.
        /// </summary>
        /// <param name="path">Path to the .shp, .shx or .dbf file for this Shapefile</param>
        /// <exception cref="ObjectDisposedException">Thrown if the Shapefile has been disposed</exception>
        /// <exception cref="ArgumentNullException">Thrown if the path parameter is null</exception>
        /// <exception cref="ArgumentException">Thrown if the path parameter is empty</exception>
        /// <exception cref="FileNotFoundException">Thrown if one of the three required files is not found</exception>
        /// <exception cref="InvalidOperationException">Thrown if an error occurs parsing file headers</exception>
        public void Open(string path)
        {
            if (_disposed)
            {
                throw new ObjectDisposedException("Shapefile");
            }

            if (path == null)
            {
                throw new ArgumentNullException("path");
            }
            if (path.Length <= 0)
            {
                throw new ArgumentException("path parameter is empty", "path");
            }

            _shapefileMainPath  = Path.ChangeExtension(path, MainPathExtension);
            _shapefileIndexPath = Path.ChangeExtension(path, IndexPathExtension);
            _shapefileDbasePath = Path.ChangeExtension(path, DbasePathExtension);
            _shapefileProjPath  = Path.ChangeExtension(path, ProjPathExtension);

            if (!File.Exists(_shapefileMainPath))
            {
                throw new FileNotFoundException("Shapefile main file not found", _shapefileMainPath);
            }
            if (!File.Exists(_shapefileIndexPath))
            {
                throw new FileNotFoundException("Shapefile index file not found", _shapefileIndexPath);
            }
            if (!File.Exists(_shapefileDbasePath))
            {
                throw new FileNotFoundException("Shapefile dBase file not found", _shapefileDbasePath);
            }

            // read projection if file exist
            if (File.Exists(_shapefileProjPath))
            {
                this.Projection = File.ReadAllText(_shapefileProjPath);
            }

            _mainStream  = File.Open(_shapefileMainPath, FileMode.Open, FileAccess.Read, FileShare.Read);
            _indexStream = File.Open(_shapefileIndexPath, FileMode.Open, FileAccess.Read, FileShare.Read);

            if (_mainStream.Length < Header.HeaderLength)
            {
                throw new InvalidOperationException("Shapefile main file does not contain a valid header");
            }

            if (_indexStream.Length < Header.HeaderLength)
            {
                throw new InvalidOperationException("Shapefile index file does not contain a valid header");
            }

            // read in and parse the headers
            byte[] headerBytes = new byte[Header.HeaderLength];
            _mainStream.Read(headerBytes, 0, Header.HeaderLength);
            _mainHeader = new Header(headerBytes);
            _indexStream.Read(headerBytes, 0, Header.HeaderLength);
            _indexHeader = new Header(headerBytes);

            // set properties from the main header
            _type        = _mainHeader.ShapeType;
            _boundingBox = new RectangleD(_mainHeader.XMin, _mainHeader.YMin, _mainHeader.XMax, _mainHeader.YMax);

            // index header length is in 16-bit words, including the header - number of
            // shapes is the number of records (each 4 workds long) after subtracting the header bytes
            _count = (_indexHeader.FileLength - (Header.HeaderLength / 2)) / 4;

            // open the metadata database
            _dBaseFileReader = new DbaseFileReader(_shapefileDbasePath);
            _dBaseHeader     = _dBaseFileReader.GetHeader();
            _dBaseEnumerator = _dBaseFileReader.GetEnumerator();

            _opened = true;
        }