ArcObjects – Converting Between Esri Geometry and WKT

Question

It seems like there is no means of converting an ArcObjects geometry to the Well-Known Text representation (and vice versa) in ArcGIS ArcObjects API. The only thing I was able to find is conversion to WKB (the IWkb interface).

Is there a way to perform conversion between geometry objects and WKT or do I have to implement it myself? I primarily aim for .NET implementation without much external dependencies.

Answer 1

Using the IWkb interface does a nice job at converting between an IGeometry and WKB. From a WKB you can use the Microsoft.SqlServer.Types library to convert a WKB to SqlGeometry then back to WKT.

IWkb wkb = geometry as (IWkb); //(Where geometry is an instance of IGeometry)
byte[] wkb_bytes = new byte[wkb.WkbSize];
int byte_count = wkb.WkbSize;
wkb.ExportToWkb(ref byte_count, out wkb_bytes[0]);

At this point you have the WKB stored in wkb_bytes. If you want to go the next step to SqlGeometry then to WKT:

SqlGeometry sqlGeom = SqlGeometry.STGeomFromWKB(new SqlBytes(wkb_bytes), srid);
string wkt = sqlGeom.ToString();