FindTransformations Method
Gets the list of applicable transformations to use when projecting geometries from the input
spatial reference to the output spatial reference.
Parameters
- inputSR
- The input spatial reference.
- outputSR
- The output spatial reference.
- extentOfInterest
- (Optional) The bounding box of the area of interest. If provided, the extent of interest is used to return the most applicable transformations for the area. The spatial reference for the extent of interest is assumed to be the . The default value is null.
- numResults
- (Optional) The number of transformations to return. If has a value of -1, then all applicable transformations are returned. The default value is 1.
- vertical
- (Optional) Specifies whether to check for vertical transformations or not. If is set to true, both and must have a vertical coordinate system. The transformation in each ProjectionTransformation in the list is a CompositeHVDatumTransformation in this case. If is set to false, the transformation in each ProjectionTransformation in the list is a CompositeGeographicTransformation. The default value is false.
Return Value
Determine Transformations
// methods need to run on the MCT
ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
//
// find the first transformation used between spatial references 4267 and 4326
//
SpatialReference sr4267 =
SpatialReferenceBuilder.CreateSpatialReference(4267);
SpatialReference sr4326 = SpatialReferences.WGS84;
List<ProjectionTransformation> transformations =
ProjectionTransformation.FindTransformations(sr4267, sr4326);
// transformations.Count = 1
ProjectionTransformation projTrans = transformations[0];
CompositeGeographicTransformation compositeGT =
projTrans.Transformation as CompositeGeographicTransformation;
GeographicTransformation gt = compositeGT[0];
// gt.Wkid = 15851
// gt.Name = "NAD_1927_To_WGS_1984_79_CONUS"
// gt.IsForward = true
//
// find the first five transformation used between spatial references 4267 and 4326
//
transformations = ProjectionTransformation.FindTransformations(
sr4267, sr4326, numResults: 5);
// transformations.Count = 5
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 15851
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_79_CONUS"
// compositeGT[0].IsForward = true
projTrans = transformations[1];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 1173
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_4"
// compositeGT[0].IsForward = true
projTrans = transformations[2];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 1172
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_3"
// compositeGT[0].IsForward = true
projTrans = transformations[3];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1241
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_NADCON"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 108190
// compositeGT[1].Name = "WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[1].IsForward = false
projTrans = transformations[4];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1241
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_NADCON"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 1515
// compositeGT[1].Name = "NAD_1983_To_WGS_1984_5"
// compositeGT[1].IsForward = true
//
// find the first transformation used between spatial
// references 4267 and 4326 within Alaska
//
// Alaska
Envelope envelope = EnvelopeBuilderEx.CreateEnvelope(-161, 61, -145, 69);
transformations = ProjectionTransformation.FindTransformations(
sr4267, sr4326, envelope);
// transformations.Count = 1
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1243
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_Alaska"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 108190
// compositeGT[1].Name = "WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[1].IsForward = false
//
// find the first geographic transformation used between two spatial references with VCS (use vertical = false)
//
SpatialReference inSR =
SpatialReferenceBuilder.CreateSpatialReference(4269, 115702);
SpatialReference outSR =
SpatialReferenceBuilder.CreateSpatialReference(4326, 3855);
// Even though each spatial reference has a VCS,
// vertical = false should return geographic transformations.
transformations = ProjectionTransformation.FindTransformations(inSR, outSR);
// transformations.Count = 1
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 108190
// compositeGT[0].Name = ""WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[0].IsForward = false
//
// find the first vertical transformation used between two spatial references with VCS (use vertical = true)
//
transformations =
ProjectionTransformation.FindTransformations(
inSR, outSR, vertical: true);
// transformations.Count = 1
projTrans = transformations[0];
CompositeHVDatumTransformation compositeHV =
projTrans.Transformation as CompositeHVDatumTransformation;
// compositeHV.Count = 2
// compositeHV[0].Wkid = 1188
// compositeHV[0].Name = "NAD_1983_To_WGS_1984_1"
// compositeHV[0].IsForward = true
// compositeHV[1].Wkid = 110019
// compositeHV[1].Name = "WGS_1984_To_WGS_1984_EGM2008_2.5x2.5_Height"
// compositeHV[1].IsForward = true
});
Determine Transformations
// methods need to run on the MCT
ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
//
// find the first transformation used between spatial references 4267 and 4326
//
SpatialReference sr4267 =
SpatialReferenceBuilder.CreateSpatialReference(4267);
SpatialReference sr4326 = SpatialReferences.WGS84;
List<ProjectionTransformation> transformations =
ProjectionTransformation.FindTransformations(sr4267, sr4326);
// transformations.Count = 1
ProjectionTransformation projTrans = transformations[0];
CompositeGeographicTransformation compositeGT =
projTrans.Transformation as CompositeGeographicTransformation;
GeographicTransformation gt = compositeGT[0];
// gt.Wkid = 15851
// gt.Name = "NAD_1927_To_WGS_1984_79_CONUS"
// gt.IsForward = true
//
// find the first five transformation used between spatial references 4267 and 4326
//
transformations = ProjectionTransformation.FindTransformations(
sr4267, sr4326, numResults: 5);
// transformations.Count = 5
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 15851
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_79_CONUS"
// compositeGT[0].IsForward = true
projTrans = transformations[1];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 1173
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_4"
// compositeGT[0].IsForward = true
projTrans = transformations[2];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 1172
// compositeGT[0].Name = "NAD_1927_To_WGS_1984_3"
// compositeGT[0].IsForward = true
projTrans = transformations[3];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1241
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_NADCON"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 108190
// compositeGT[1].Name = "WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[1].IsForward = false
projTrans = transformations[4];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1241
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_NADCON"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 1515
// compositeGT[1].Name = "NAD_1983_To_WGS_1984_5"
// compositeGT[1].IsForward = true
//
// find the first transformation used between spatial
// references 4267 and 4326 within Alaska
//
// Alaska
Envelope envelope = EnvelopeBuilderEx.CreateEnvelope(-161, 61, -145, 69);
transformations = ProjectionTransformation.FindTransformations(
sr4267, sr4326, envelope);
// transformations.Count = 1
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 2
// compositeGT[0].Wkid = 1243
// compositeGT[0].Name = "NAD_1927_To_NAD_1983_Alaska"
// compositeGT[0].IsForward = true
// compositeGT[1].Wkid = 108190
// compositeGT[1].Name = "WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[1].IsForward = false
//
// find the first geographic transformation used between two spatial references with VCS (use vertical = false)
//
SpatialReference inSR =
SpatialReferenceBuilder.CreateSpatialReference(4269, 115702);
SpatialReference outSR =
SpatialReferenceBuilder.CreateSpatialReference(4326, 3855);
// Even though each spatial reference has a VCS,
// vertical = false should return geographic transformations.
transformations = ProjectionTransformation.FindTransformations(inSR, outSR);
// transformations.Count = 1
projTrans = transformations[0];
compositeGT = projTrans.Transformation as CompositeGeographicTransformation;
// compositeGT.Count = 1
// compositeGT[0].Wkid = 108190
// compositeGT[0].Name = ""WGS_1984_(ITRF00)_To_NAD_1983"
// compositeGT[0].IsForward = false
//
// find the first vertical transformation used between two spatial references with VCS (use vertical = true)
//
transformations =
ProjectionTransformation.FindTransformations(
inSR, outSR, vertical: true);
// transformations.Count = 1
projTrans = transformations[0];
CompositeHVDatumTransformation compositeHV =
projTrans.Transformation as CompositeHVDatumTransformation;
// compositeHV.Count = 2
// compositeHV[0].Wkid = 1188
// compositeHV[0].Name = "NAD_1983_To_WGS_1984_1"
// compositeHV[0].IsForward = true
// compositeHV[1].Wkid = 110019
// compositeHV[1].Name = "WGS_1984_To_WGS_1984_EGM2008_2.5x2.5_Height"
// compositeHV[1].IsForward = true
});
Target Platforms: Windows 11, Windows 10
ArcGIS Pro version: 3 or higher.