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POGeoTrans p/invoke wrapper NullReferenceException
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copied!<p>I'm trying to expose methods I need to call from the GeoTrans c++ library but, am running into issues. Any help would be great!</p> <p>I have the following c++ file that i'm running nmake against to compile into a dll.</p> <pre><code>#include <iostream> #include "CoordinateConversionService.h" #include "CoordinateSystemParameters.h" #include "GeodeticParameters.h" #include "CoordinateTuple.h" #include "GeodeticCoordinates.h" #include "CartesianCoordinates.h" #include "Accuracy.h" #include "MGRSorUSNGCoordinates.h" #include "UTMParameters.h" #include "UTMCoordinates.h" #include "CoordinateType.h" #include "HeightType.h" #include "CoordinateConversionException.h" using MSP::CCS::Precision; int main(int argc, char **argv){} extern "C"__declspec(dllexport) void __stdcall convertGeodeticToGeocentric(const double lat,const double lon, const double height, double& x, double& y, double& z) { MSP::CCS::CoordinateSystemParameters geocentricParameters(MSP::CCS::CoordinateType::geocentric); MSP::CCS::CoordinateConversionService ccs( "WGE", &geodeticParameters, "WGE", &geocentricParameters ); MSP::CCS::Accuracy sourceAccuracy; MSP::CCS::Accuracy targetAccuracy; MSP::CCS::GeodeticCoordinates sourceCoordinates(MSP::CCS::CoordinateType::geodetic, lon, lat, height); MSP::CCS::CartesianCoordinates targetCoordinates(MSP::CCS::CoordinateType::geocentric); ccs.convertSourceToTarget( &sourceCoordinates, &sourceAccuracy, targetCoordinates, targetAccuracy ); x = targetCoordinates.x(); y = targetCoordinates.y(); z = targetCoordinates.z(); } extern "C"__declspec(dllexport) void __stdcall convertGeocentricToGeodetic(const double x, const double y, const double z, double& lat,double& lon, double& height) { MSP::CCS::CoordinateSystemParameters geocentricParameters(MSP::CCS::CoordinateType::geocentric); MSP::CCS::GeodeticParameters geodeticParameters(MSP::CCS::CoordinateType::geodetic, MSP::CCS::HeightType::ellipsoidHeight); MSP::CCS::CoordinateConversionService ccs( "WGE", &geocentricParameters, "WGE", &geodeticParameters ); MSP::CCS::Accuracy sourceAccuracy; MSP::CCS::Accuracy targetAccuracy; MSP::CCS::CartesianCoordinates sourceCoordinates(MSP::CCS::CoordinateType::geocentric, x, y, z); MSP::CCS::GeodeticCoordinates targetCoordinates; ccs.convertSourceToTarget( &sourceCoordinates, &sourceAccuracy, targetCoordinates, targetAccuracy ); lat = targetCoordinates.latitude(); lon = targetCoordinates.longitude(); height = targetCoordinates.height(); } extern "C"__declspec(dllexport) void __stdcall convertGeocentricToUTM(const double x, const double y, const double z, long& zone, char& hemisphere, double& easting, double& northing) { MSP::CCS::CoordinateSystemParameters geocentricParameters(MSP::CCS::CoordinateType::geocentric); MSP::CCS::UTMParameters utmParameters(MSP::CCS::CoordinateType::universalTransverseMercator, 1, 0); MSP::CCS::CoordinateConversionService ccs( "WGE", &geocentricParameters, "WGE", &utmParameters ); MSP::CCS::Accuracy sourceAccuracy; MSP::CCS::Accuracy targetAccuracy; MSP::CCS::CartesianCoordinates sourceCoordinates(MSP::CCS::CoordinateType::geocentric, x, y, z); MSP::CCS::UTMCoordinates targetCoordinates; ccs.convertSourceToTarget( &sourceCoordinates, &sourceAccuracy, targetCoordinates, targetAccuracy ); zone = targetCoordinates.zone(); hemisphere = targetCoordinates.hemisphere(); easting = targetCoordinates.easting(); northing = targetCoordinates.northing(); } extern "C"__declspec(dllexport) void __stdcall convertGeocentricToMGRS(const double x, const double y, const double z, char*& mgrsString, Precision::Enum& precision) { MSP::CCS::CoordinateSystemParameters geocentricParameters(MSP::CCS::CoordinateType::geocentric); MSP::CCS::CoordinateSystemParameters mgrsParameters(MSP::CCS::CoordinateType::militaryGridReferenceSystem); MSP::CCS::CoordinateConversionService ccs( "WGE", &geocentricParameters, "WGE", &mgrsParameters ); MSP::CCS::Accuracy sourceAccuracy; MSP::CCS::Accuracy targetAccuracy; MSP::CCS::CartesianCoordinates sourceCoordinates(MSP::CCS::CoordinateType::geocentric, x, y, z); MSP::CCS::MGRSorUSNGCoordinates targetCoordinates; ccs.convertSourceToTarget( &sourceCoordinates, &sourceAccuracy, targetCoordinates, targetAccuracy ); mgrsString = targetCoordinates.MGRSString(); precision = targetCoordinates.precision(); } </code></pre> <p>I then have the following p/invoke calls in my c# class..</p> <pre><code>[DllImport("CoordinateConversionWrapper.dll")] private static extern void convertGeodeticToGeocentric(double lat, double lon, double height, ref double x, ref double y, ref double z); [DllImport("CoordinateConversionWrapper.dll")] private static extern void convertGeocentricToMGRS(double x, double y, double z, ref char[] mgrsString, Precision precision); </code></pre> <p>Calling any of the above p/invoke methods results in a NullReferenceException. It seems like the issue is within the c++ code itself but, not being a c++ expert I'm not sure what the issue is...</p> <p>Please Help!!</p>

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