All Cadcorp SIS API Methods

CreateFilteredOverlay Method

Description

Create a phased overlay with specified filters and spatial filters applied.

Syntax

Public Function CreateFilteredOverlay( _
   ByVal oldPos As Integer, _
   ByVal newPos As Integer, _
   ByVal filter As String, _
   ByVal locus As String _
) As Integer

Parameters

oldPos

The position in the overlays list of the overlay to be scanned.

newPos

The position of the new overlay in the overlays list.

filter

Optionally, specify a named filter which items must pass to be included in the scan.
Use an empty string to omit the filter.

locus

Optionally, specify a named Spatial Filter which items must fall within to be included in the scan.
Use an empty string to omit the Spatial Filter.

Remarks

Instead of using a named filter in the filter parameter a SQL statement filter can be used to create a filtered overlay from a database (PostGIS, Oracle, SQL server, etc.)

Available: GEO  D OD OM SISpy

Group:

• Overlay Methods

Example

sis.CreateFilteredOverlay(2, 5, "Building", "Conservation")

This example creates a new overlay at position 5 in the overlay order. The new overlay contains all items from overlay 2 that pass both the Building filter and the Conservation Spatial Filter.

The following example shows a SQL statement used instead of a named filter:

sis.CreateFilteredOverlay(0, 0, "sis_fc = 21001", "")

This example will generate a new overlay from a database in the same location as the old overlay, filtered for the sis_fc property value 21001.