GetBlobExtent Method

Description

Gets the extents of a Blob string, within a Coordinate Reference System

Syntax

Visual Basic
Public Function GetBlobExtent( _
   ByVal blob As String, _
   ByVal prj As String, _
   ByVal fmt As Integer _
) As String

Parameters

blob
The stored Item Blob string.
 
prj
The named Coordinate Reference System of the stored Item Blob. This can be defined as:
  • OGC URNs (eg 'urn:ogc:def:crs:OGC:1.3:CRS84')
  • EPSG URNs (eg 'urn:ogc:def:crs:EPSG::27700')
  • EPSG code strings (eg 'EPSG:27700')
  • EPSG URLs (eg 'http://www.example.com/epsg#27700' or 'http://www.example.com/epsg.xml#27700')
  • EPSG codes as a simple string (eg '27700')
If blank, this will default to the current 'axes' CRS.
 
precision%
Number of decimal places to use for coordinates when generating GeoJSON or OGC WKT representations (Range is 1 to 15 (inclusive))
 
fmt
The format of the stored Item Blob.

SIS_BLOB_OGIS_WKT 2 = OGC Well-Known-Text format
SIS_BLOB_OGIS_GML 3 = OGC Geographic Markup Language
SIS_BLOB_GEOJSON 6 = Geographic Objects for JSON format

Return Type

A comma-delimited string containing a pair of x, y and z co-ordinates describing the extents. Use SplitExtent to get the pair of x, y and z values themselves.

Remarks

Available: GEO D OD OM SISpy

Group:

Example

sis.GetBlobExtent ( blob, "*APrjNatGrid", 0 )

Returns the extent of the value of blob within the National Grid coordinate reference system