FDO API Reference Feature Data Objects

FdoISpatialContextReader Class Reference

#include <ISpatialContextReader.h>

Inherits FdoIDisposable.

Inherited by FdoXmlSpatialContextReader.

Inheritance diagram for FdoISpatialContextReader:

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List of all members.

Detailed Description

The FdoISpatialContextReader interface provides forward-only, read-only functionality for enumerating spatial contexts. A reference to an FdoISpatialContextReader is returned from the GetSpatialContexts command. The initial position of the FdoISpatialContextReader interface is prior to the first item. Thus, you must call ReadNext to begin accessing any data.

Definition at line 34 of file ISpatialContextReader.h.


Public Member Functions

virtual FDO_API void Dispose ()=0
 Closes the FdoISpatialContextReader object, freeing any resources it may be holding.
virtual FDO_API FdoStringGetCoordinateSystem ()=0
 Gets the name of the coordinate system of the spatial context currently being read. If the result is a null or empty string, the coordinate system is unknown to the spatial context.
virtual FDO_API FdoStringGetCoordinateSystemWkt ()=0
 Gets the name of the coordinate system in OpenGIS SRS WKT format of the spatial context currently being read. If the result is an empty string, the coordinate system WKT description is not available.
virtual FDO_API FdoStringGetDescription ()=0
 Gets the description of the spatial context currently being read.
virtual FDO_API FdoByteArrayGetExtent ()=0
 Gets the extent of the spatial context currently being read as a byte array in FGF format.
virtual FDO_API FdoSpatialContextExtentType GetExtentType ()=0
 Gets the extent type of the spatial context currently being read.
virtual FDO_API FdoStringGetName ()=0
 Gets the name of the spatial context currently being read.
virtual FDO_API const double GetXYTolerance ()=0
 Gets the tolerance value for XY ordinates of the spatial context currently being read. Tolerances are used in some geometric tests, mostly for equality between coordinates. This occurs frequently in spatial queries, especially with "on boundary" or "just touching" conditions. It is also an objective amount that can be used when formulating step distances for parametric curve interpolation.
virtual FDO_API const double GetZTolerance ()=0
 Gets the tolerance value for Z ordinates of the spatial context currently being read. Tolerances are used in some geometric tests, mostly for equality between coordinates. This occurs a frequently in spatial queries, especially with "on boundary" or "just touching" conditions. It is also an objective amount that can be used when formulating step distances for parametric curve interpolation.
virtual FDO_API const bool IsActive ()=0
 Returns true if the spatial context currently being read is the active spatial context.
virtual FDO_API bool ReadNext ()=0
 Advances the reader to the next item. The default position of the reader is prior to the first item. Thus, you must call ReadNext to begin accessing any data.

The documentation for this class was generated from the following file:
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