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As asked on the esri forum here, we are trying to convert a geometry from any spatial reference to any other spatial reference. We have tried the default IGeometry.Project(target_spatial_reference) but with no success. We then turned our attention to IGeometry.ProjectEx(...), but some of the sample data we have does not use a well-nknownn ID (FactoryCode) and we can't find a canned, out-of-the-box GeoTransformation to convert our geometry.

We did follow the recommendations in both responses in this other thread here, but with no succes.

Does anybody here know of an esri API that can project a geometry from any spatial reference to any other spatial reference?

Or, can anybody point us to a code sample or algorithm to properly and accurately project a geometry to/from any spatial reference?

Thanks in advance for your help,


share|improve this question
Assuming you had a resource that gave you a list of all the applicable geotransformations for transforming between two different datums, how would you expect the algorithm to choose the "best" one? I wonder if the folks at have considered providing an API whereby you could zoom in on an area on the map and see a list of geotransforms and/or projections. – Kirk Kuykendall Oct 19 '12 at 21:07

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