Migrating. Net code from ArcGIS 8.3 to 9.0

Migrating. Net code from ArcGIS 8.3 to 9.0

ArcGIS 9.0 introduces a change in the structure of the type libraries that define the ArcObjects classes and interfaces. these changes may require you to make changes in turn to your existing ArcObjects developments, regardless of the development language you are using.

You can find out information about the reasons for these changes and also the details of the changes in the topic migrating from 8.3 to 9.0.

In addition, you may encounter issues which are special ly relevant to the. NET environment.

1. Non-OLE Automation compliant types
2. Changes to members on class interfaces
3. Changes to utility and base classes
4. Capitalization changes

 

1. Non-OLE Automation compliant types

   The interfaces in ArcObjects contain a few members which are not ole-compliant, for example the C-style array parameters used in many ry members. as COM InterOP relies on data types being ole-compliant, these members are unfortunately not useable in. net.

   At ArcGIS 8.3, ESRI manipulated the intermediate language (IL) of the InterOP assemblies in order to perform data type conversion and allow the members to be used in. net successfully. however, at 9.0, with the introduction of other supported environments such as Java, a more reliable and pervasive solution was required to allow access to non-ole-compliant members.

   In most cases, supplemental interfaces have been added which have members rewritten to use OLE-compliant data types. for example, for Members which used C-style arrays, alternative members have been added which use the OLE Automation safearray data type to handle the arrays. if you have used these members in your. net code with ArcGIS 8.3, you should change your code to use the new OLE Automation compatible interfaces when working against ArcGIS 9.0. this subject is discussed, with an example of ienvelope: definefrompoints, In the interoperating with COM topic in. NET Programming Techniques section of the developer help.

   These supplemental interfaces use the naming convention I <Interfacename> Gen. one exception to this naming convention is the igeometrybridge interface. in order to avoid the 'bloating 'of geometry classes with new interfaces, Ole-compliant versions of specified geometry members can be found grouped together on the igeometrybridge interface of the geometryenvironment class.

   The table below gives a listing of the ole-compliant interfaces and members, and their compliant equivalents.

    

   Interface	Non-compliant Member	Interface of equivalent compliant Member	9.0 ESRI. ArcGIS namespace
   Iaffinetransformation2d	Definefromcontrolpoints	Iaffinetransformation2d3gen	Geometry
   Iaffinetransformation2d3	Defineconformalfromcontrolpoints	Iaffinetransformation2d3gen	Geometry
   Iaffinetransformation2d3	Querylinearcoefficients	Iaffinetransformation2d3gen	Geometry
   Iaffinetransformation2d3	Setlinearcoefficients	Iaffinetransformation2d3gen	Geometry
   Ibeziercurve	Querycoords	Ibeziercurvegen	Geometry
   Ibeziercurve	Putcoords	Ibeziercurvegen	Geometry
   Iclassify	Classbreaks	Iclassifygen: classify	Esrisystem
   Iclassify	Sethistogramdata	Iclassifygen: classify	Esrisystem
   Ienvelope	Definefrompoints	Ienvelopegen	Geometry
   Ienvelope	Definefromwkspoints	Ienvelopegen	Geometry
   Iforwardstar	Queryadjacentedges	Iforwardstargen	Geodatabase
   Iforwardstar	Queryadjacentjunctions	Iforwardstargen	Geodatabase
   Igeometrycollection	Addgeometries	Igeometrybridge	Geometry
   Igeometrycollection	Insertgeometries	Igeometrybridge	Geometry
   Igeometrycollection	Querygeometries	Igeometrybridge	Geometry
   Igeometrycollection	Setgeometries	Igeometrybridge	Geometry
   Imultipatch	Querybeginningrings	Igeometrybridge	Geometry
   Imultipatch	Queryfollowingrings	Igeometrybridge	Geometry
   Inetelementbarriers	Setbarriers	Inetelementbarriersgen	Networkanalysis
   Inetelementbarriers2	Setbarriersbyeid	Inetelementbarriersgen	Networkanalysis
   Inetsolverweights	Setfilterranges	Inetsolverweightsgen	Networkanalysis
   Ipiecewisetransformation	Definefromcontrolpoints	Ipiecewisetransformationgen	Editorext
   Ipointcollection	Addpoints	Igeometrybridge	Geometry
   Ipointcollection	Insertpoints	Igeometrybridge	Geometry
   Ipointcollection	Querypoints	Igeometrybridge	Geometry
   Ipointcollection	Replacepoints	Igeometrybridge	Geometry
   Ipointcollection	Setpoints	Igeometrybridge	Geometry
   Ipointcollection2	Getpoints	Igeometrybridge	Geometry
   Ipointcollection4	Addwkspointzs	Igeometrybridge	Geometry
   Ipointcollection4	Querywkspointzs	Igeometrybridge	Geometry
   Ipointcollection4	Setwkspointzs	Igeometrybridge	Geometry
   Iprojectedcoordinatesystem	Forward	Iprojectedcoordinatesystem4gen	Geometry
   Iprojectedcoordinatesystem	Getparameters	Iprojectedcoordinatesystem4gen	Geometry
   Iprojectedcoordinatesystem	Inverse	Iprojectedcoordinatesystem4gen	Geometry
   Iprojectedcoordinatesystem2	Inversewithshift	Iprojectedcoordinatesystem4gen	Geometry
   Iprojection	Getdefaparameparameters	Iprojectiongen	Geometry
   Iprojectivetransformation2d	Definefromcontrolpoints	Iprojectivetransformation2dgen	Geometry
   Iprojectivetransformation2d	Settransformationparameters	Iprojectivetransformation2dgen	Geometry
   Iprojectivetransformation2d	Querytransformationparameters	Iprojectivetransformation2dgen	Geometry
   Isegment	Densify	Igeometrybridge	Geometry
   Isegmentcollection	Addsegments	Igeometrybridge	Geometry
   Isegmentcollection	Insertsegments	Igeometrybridge	Geometry
   Isegmentcollection	Querysegments	Igeometrybridge	Geometry
   Isegmentcollection	Replacesegments	Igeometrybridge	Geometry
   Isegmentcollection	Setsegments	Igeometrybridge	Geometry
   Ispatialreference2	Applyprecision	Ispatialreference2gen	Geometry
   Ispatialreference2	Applyxyprecision	Ispatialreference2gen	Geometry
   Itopologicaloperator2	Constructbuffers	Igeometrybridge	Geometry
   Itraceflowsolver	Findpath	Itraceflowsolvergen	Networkanalysis
   Itraceflowsolver	Putedgeorigins	Itraceflowsolvergen	Networkanalysis
   Itraceflowsolver	Putjunctionorigins	Itraceflowsolvergen	Networkanalysis
   Itraceflowsolver2	Findsource	Itraceflowsolvergen	Networkanalysis
   Itransformation	Transformmeasuresff	Itransformationgen	Geometry
   Itransformation	Transformmeasuresfi	Itransformationgen	Geometry
   Itransformation	Transformmeasuresif	Itransformationgen	Geometry
   Itransformation	Transformmeasureⅱ	Itransformationgen	Geometry
   Itransformation	Transformpointsff	Itransformationgen	Geometry
   Itransformation	Transformpointsfi	Itransformationgen	Geometry
   Itransformation	Transformpointsif	Itransformationgen	Geometry
   Itransformation	Transformpointⅱ	Itransformationgen	Geometry
   Itransformation3d	Transform	Itransformation3dgen	Geometry
   Itransformationmethod	Definefromcontrolpoints	Itransformationmethodgen	Editorext
   Iutilitynetwork	Establishflowdirection	Iutilitynetworkgen	Geodatabase
   Iutilitynetwork2	Partialestablishflowdirection	Iutilitynetworkgen	Geodatabase

   NoteThe iactiveviewgen interface provides generic versions of the exportframe and output members; these members are essential for use from the Java API, but you will find the original iactiveview members are useable from. net.

   The wkspointsmap2pixeltransform member of irastergeometryproc2 is not suitable for use from. Net; however, this method is superseded by irastergeometryproc3: pointsmap2pixeltransform.

   The numbers and numbers members of ipolympus Gon, and also the getconnectedcomponents, numbers, numbers, and numbers members of ipolympus gon2 have no safearray alternative in ArcGIS 9.0; future releases may include generic versions of these members.

2. Changes to members on class interfaces

   This issue affects C # code which declares variables as a class interface rather than a class or interface type, for example envelope versus envelopeclass or ienvelope. at ArcGIS 9.0, the inherited types of the class interface may have changed. the details of why this change occurred are described below the table.

   The list below details which class interfaces are affected by this issue. When recompiling code using these class interfaces you may need to make changes to your code.

    

   Class Interface	9.0 ESRI. ArcGIS namespace
   Abridgedmolodenskytransformation	Geometry
   Affinetransformation2d	Geometry
   Affinetransformation3d	Geometry
   Beziercurve	Geometry
   Compositegeotransformation	Geometry
   Coordinatetransformation	Surveyext
   Coordinateframetransformation	Geometry
   Definedinterval	Esrisystem
   Displaytransformation	Display
   Envelope	Geometry
   Equalinterval	Esrisystem
   Forwardstar	Geodatabase
   Geocentrictranslation	Geometry
   Geographiccoordinatesystem	Geometry
   Harntransformation	Geometry
   Helmerttransformation2d	Surveyext
   Longituderotationtransformation	Geometry
   Molodenskybadekastransformation	Geometry
   Molodenskytransformation	Geometry
   Nadcontransformation	Geometry
   Naturalbreaks	Esrisystem
   Netelementbarriers	Networkanalysis
   Ntv2transformation	Geometry
   Piecewisetransformation	Editorext
   Piecewisetransformationmethod	Editorext
   Positionvectortransformation	Geometry
   Projectedcoordinatesystem	Geometry
   Projection	Geometry
   Projectivetransformation2d	Geometry
   Quantile	Esrisystem
   Simpletransformation2d	Surveyext
   Standarddeviation	Esrisystem
   Traceflowsolver	Networkanalysis
   Unknowncoordinatesystem	Geometry
   Utilitynetwork	Geodatabase

   As explained in the class interfaces topic, the default Interface of a COM class is automatically added to each RCW class interface. however, ArcGIS classes generally have the iunknown interface as the default interface, and this interface is not exposed via COM InterOP. if the default Interface is iunknown or idispatch, the next listed interface on the com class is implemented by the class interface instead. for example, at ArcGIS 8.3 you cocould use code like that below to instantiate a new envelopeclass using ienvelope, as ienvelope is the first listed interface (after the default, iunknown) on the envelope com class, and is therefore implemented by the class interface envelope.

   [C #]

   IEnvelope env = new Envelope();

   However at ArcGIS 9.0, in order to allow the Java API to function correctly, some com classes had interfaces added to the top of the interface list. for example, the envelope com class gained as it implements first listed interface (after the default iunknown), ienvelopegen. this means that at ArcGIS 9.0, the envelope class interface implements ienvelopegen rather than ienvelope, and the above Code will no longer be legal. however, it can be replaced with either of the alternatives below:

   [C #]

   IEnvelope env = new EnvelopeClass();IEnvelope env = new Envelope() as IEnvelope;

   (To complicate matters, the equivalent VB. net code wocould not cause a compile error. this is because the VB. net compiler interprets the code as a command to Qi at runtime for the ienvelope interface, which of course is a successful call as the envelopeclass does implement ienvelope. C # does not allow these 'implicit casts ').

3. Changes to Utility Classes

   The ESRI. arcGIS. utility. catids namespace provides classes representing each of the ArcGIS component categories. each class knows its catid and exposes static methods (register and unregister) which allow you to add and remove a class from the component category.

   At ArcGIS 8.3, the catids namespace and contents were provided as a developer sample. at ArcGIS 9.0, this was converted to a core assembly, present in the/DOTNET subfolder of your ArcGIS installation along with the InterOP assemblies. in addition to this, some classes were renamed for consistency with the underlying catid name. for example, at 8.3, you may have used the mxcommand class; at 9.0 this class is called mxcommands. in addition to these changes, new classes were added to represent the new 9.0 categories.

   The migrating from 8.3 to 9.0 topic lists all the classes affected.

4. Capitalization changes

   Certain structure definitions are originally defined outside of the ESRI libraries; for example, the tagrect structure is originally defined in the Windows API. the change in the structure of ESRI's libraries between 8.3 and 9.0, the original location of such definitions, and the fact that the midl compiler used to compile the libraries is case-insensitive, has resulted in certain structures changing capitalization.

   As C # is a case-sensitive language, any changes in the capitalization if class, interface, Member, parameter or structure names will need to be reflected in C # source code. visual Basic. net is not case-sensitive, and will automatically correct any such case changes.

   The table below gives details of such changes.

    

   8.3 Name	9.0 name	9.0 ESRI. ArcGIS namespace
   Tagpoint. x	Tagpoint. x	Display
   Tagpoint. Y	Tagpoint. Y	Display
   Tagproppageinfo. Size	Tagproppageinfo. Size	Framework
   Tagrect. Left	Tagrect. Left	Display
   Tagrect. Right	Tagrect. Right	Display
   Tagrect. Top	Tagrect. Top	Display
   Tagstatstg. Type	Tagstatstg. Type	Esrisystem
   Tagstatstg. CLSID	Tagstatstg. CLSID	Esrisystem