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I need to take an uploaded polygon shapefile and extract some information from it, including the lat/long positions of the centroids of the features.

Using DotSpatial I attempt to Reproject the shapefile into WGS 1984 to get latitude and longitude

if (!shapefile.Projection.IsLatLon)
{
    shapefile.Reproject(
        KnownCoordinateSystems.Geographic.World.WGS1984);
}

but the coordinates I get out land in South Dakota when they should be in Colorado.

Some centroids prior to reprojection:

{(3118274.90587493, 1458696.3665899)}
{(3118274.90587493, 1458696.3665899)}

The coordinates in South Dakota that I get after running the code above:

{(-104.040689162766, 43.4531513926421)}
{(-104.040690516737, 43.4529967532427)}

Am I missing a step?

EDIT: Contents of .prj file PROJCS["NAD_1983_HARN_StatePlane_Colorado_North_FIPS_0501_Feet",GEOGCS["GCS_North_American_1983_HARN",DATUM["D_North_American_1983_HARN",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",3000000.000316083],PARAMETER["False_Northing",999999.999996],PARAMETER["Central_Meridian",-105.5],PARAMETER["Standard_Parallel_1",39.71666666666667],PARAMETER["Standard_Parallel_2",40.78333333333333],PARAMETER["Latitude_Of_Origin",39.33333333333334],UNIT["Foot_US",0.3048006096012192]],VERTCS["NAD_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PARAMETER["Vertical_Shift",0.0],PARAMETER["Direction",1.0],UNIT["Meter",1.0]]

  • What is the crs of your source data? Did you specify it somewhere in your code? Is there a correctly defined .prj file with the shapefile? – FSimardGIS Dec 19 '18 at 17:42
  • @FSimardGIS I am not specifying the source CRS in my code but the shapefile includes a .prj, the contents of which I have put in the question. – Nick Dec 19 '18 at 17:55

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