MapScript Objects
For a complete MapScript object, variable, and method guide see the latest on the MapServer documentation web site page or Sean Gillies' reference guide (http://zcologia.com/mapserver).
Class diagrams are also available from these web sites:
Classes within the map file can be accessed as objects in MapScript. In fact, there are more objects to handle
than you normally see, because MapServer does a lot of the work with
them behind the scenes. The main part of a MapScript application is the
map object (mapObj
). The mapObj
can have
many layer objects (layerObj
) as well as legend (legendObj
), scale bar (scalebarObj
), and reference map (referenceMapObj
) objects. Figure 14-1 shows a diagram of
how these objects are hierarchically structured.
The main object is the mapObj
.
You can add a layerObj
, classObj
, and styleObj
to the mapObj
. Other
objects should never be explicitly created, such as webObj
, scalebarObj
, legendObj
, and colorObj
. These are already part of the mapObj
, and constructing new objects for them
will fail. If you get segmentation faults from MapScript, this may be
the cause.
All the attributes of objects that you normally see in the map file are available for manipulation through MapScript.
Using the MapScript API is best understood by walking through some simple examples.
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