/// <summary>
/// Checks if a spatial reference is unprojected WGS84.
/// </summary>
/// <param name="sr">spatial reference to check</param>
/// <returns>true if the spatial reference is WGS84, false if not</returns>
public static bool IsWGS84(ISpatialReference sr)
{
IClone wgs84 = (IClone)EsriUtilities.GetWGS84();
IClone targetDatum = (IClone)EsriUtilities.GetDatum(sr);
return((targetDatum).IsEqual(wgs84));
}
/// <summary>
/// Gets a list of all geotransforms that use the provided spatial reference and unprojected
/// WGS84
/// </summary>
/// <param name="sr">spatial reference to look for</param>
/// <returns>List of applicable IGeoTransformation objects</returns>
public static List <IGeoTransformation> GetTransformations(ISpatialReference sr)
{
GeoTransformationComparer transComparer = new GeoTransformationComparer();
IClone wgs84 = (IClone)EsriUtilities.GetWGS84();
IClone targetDatum = (IClone)EsriUtilities.GetDatum(sr);
List <IGeoTransformation> transList = new List <IGeoTransformation>();
ISpatialReferenceFactory2 srFactory = new SpatialReferenceEnvironmentClass();
ISet transSet = srFactory.GetPredefinedGeographicTransformations();
IGeoTransformation trans;
ISpatialReference fromDatum;
ISpatialReference toDatum;
for (int i = 0; i < transSet.Count; i++)
{
trans = (IGeoTransformation)transSet.Next();
trans.GetSpatialReferences(out fromDatum, out toDatum);
if (wgs84.IsEqual((IClone)fromDatum) || wgs84.IsEqual((IClone)toDatum))
{
if (targetDatum.IsEqual((IClone)fromDatum) || targetDatum.IsEqual((IClone)toDatum))
{
transList.Add(trans);
}
}
}
transList.Sort(transComparer.Compare);
return(transList);
}