C# Class Mapsui.Providers.Shapefile.ShapeFile

Shapefile dataprovider

The ShapeFile provider is used for accessing ESRI ShapeFiles. The ShapeFile should at least contain the [filename].shp, [filename].idx, and if feature-data is to be used, also [filename].dbf file.

The first time the ShapeFile is accessed, Mapsui will automatically create a spatial index of the shp-file, and save it as [filename].shp.sidx. If you change or update the contents of the .shp file, delete the .sidx file to force Mapsui to rebuilt it. In web applications, the index will automatically be cached to memory for faster access, so to reload the index, you will need to restart the web application as well.

M and Z values in a shapefile is ignored by Mapsui.

Inheritance: IProvider, IDisposable

Mostra file Open project: pauldendulk/Mapsui Class Usage Examples

Public Methods

Method	Description
Dispose ( ) : void	Disposes the object
GetExtents ( ) : BoundingBox	Returns the extents of the datasource
GetFeature ( uint rowId, IFeatures feature = null ) : IFeature	Gets a datarow from the datasource at the specified index belonging to the specified datatable
GetFeatureCount ( ) : int	Returns the total number of features in the datasource (without any filter applied)
GetFeaturesInView ( BoundingBox box, double resolution ) : IEnumerable
GetGeometriesInView ( BoundingBox bbox ) : Collection	Returns geometries whose bounding box intersects 'bbox' Please note that this method doesn't guarantee that the geometries returned actually intersect 'bbox', but only that their boundingbox intersects 'bbox'. This method is much faster than the QueryFeatures method, because intersection tests are performed on objects simplifed by their boundingbox, and using the Spatial Index.
GetGeometry ( uint oid ) : IGeometry	Returns the geometry corresponding to the Object ID
GetObjectIDsInView ( BoundingBox bbox ) : Collection	Returns geometry Object IDs whose bounding box intersects 'bbox'
RebuildSpatialIndex ( ) : void	Forces a rebuild of the spatial index. If the instance of the ShapeFile provider uses a file-based index the file is rewritten to disk.
ShapeFile ( string filename, bool fileBasedIndex = false ) : System	Initializes a ShapeFile DataProvider. If FileBasedIndex is true, the spatial index will be read from a local copy. If it doesn't exist, it will be generated and saved to [filename] + '.sidx'. Using a file-based index is especially recommended for ASP.NET applications which will speed up start-up time when the cache has been emptied.

Private Methods

Method	Description
Close ( ) : void	Closes the datasource
CreateSpatialIndex ( ) : QuadTree	Generates a spatial index for a specified shape file.
CreateSpatialIndexFromFile ( string filename ) : QuadTree	Loads a spatial index from a file. If it doesn't exist, one is created and saved
Dispose ( bool disposing ) : void
GetAllFeatureBoundingBoxes ( ) : IEnumerable	Reads all boundingboxes of features in the shapefile. This is used for spatial indexing.
GetFeaturePrivate ( uint rowId, IFeatures dt ) : IFeature
GetShapeIndex ( uint n ) : int	Gets the file position of the n'th shape
InitializeShape ( string filename, bool fileBasedIndex ) : void
LoadSpatialIndex ( bool loadFromFile ) : void
LoadSpatialIndex ( bool forceRebuild, bool loadFromFile ) : void
Open ( ) : void	Opens the datasource
ParseHeader ( ) : void	Reads and parses the header of the .shx index file
ParseProjection ( ) : void	Reads and parses the projection if a projection file exists
ReadGeometry ( uint oid ) : Geometry	Reads and parses the geometry with ID 'oid' from the ShapeFile Filtering is not applied to this method
ReadIndex ( ) : int[]	Reads the record offsets from the .shx index file and returns the information in an array
SwapByteOrder ( int i ) : int	Swaps the byte order of an int32

Method Details

Dispose() public method

Disposes the object

public Dispose ( ) : void
return	void

GetExtents() public method

Returns the extents of the datasource

public GetExtents ( ) : BoundingBox
return	BoundingBox

GetFeature() public method

Gets a datarow from the datasource at the specified index belonging to the specified datatable

public GetFeature ( uint rowId, IFeatures feature = null ) : IFeature
rowId	uint
feature	IFeatures	Datatable to feature should belong to.
return	IFeature

GetFeatureCount() public method

Returns the total number of features in the datasource (without any filter applied)

public GetFeatureCount ( ) : int
return	int

GetFeaturesInView() public method

public GetFeaturesInView ( BoundingBox box, double resolution ) : IEnumerable
box	BoundingBox
resolution	double
return	IEnumerable

GetGeometriesInView() public method

Returns geometries whose bounding box intersects 'bbox'

Please note that this method doesn't guarantee that the geometries returned actually intersect 'bbox', but only that their boundingbox intersects 'bbox'.

This method is much faster than the QueryFeatures method, because intersection tests are performed on objects simplifed by their boundingbox, and using the Spatial Index.

public GetGeometriesInView ( BoundingBox bbox ) : Collection
bbox	BoundingBox
return	Collection

GetGeometry() public method

Returns the geometry corresponding to the Object ID

public GetGeometry ( uint oid ) : IGeometry
oid	uint	Object ID
return	IGeometry

GetObjectIDsInView() public method

Returns geometry Object IDs whose bounding box intersects 'bbox'

public GetObjectIDsInView ( BoundingBox bbox ) : Collection
bbox	BoundingBox
return	Collection

RebuildSpatialIndex() public method

Forces a rebuild of the spatial index. If the instance of the ShapeFile provider uses a file-based index the file is rewritten to disk.

public RebuildSpatialIndex ( ) : void
return	void

ShapeFile() public method

Initializes a ShapeFile DataProvider.

If FileBasedIndex is true, the spatial index will be read from a local copy. If it doesn't exist, it will be generated and saved to [filename] + '.sidx'.

Using a file-based index is especially recommended for ASP.NET applications which will speed up start-up time when the cache has been emptied.

public ShapeFile ( string filename, bool fileBasedIndex = false ) : System
filename	string	Path to shape file
fileBasedIndex	bool	Use file-based spatial index
return	System