Convert SQL geography to C#

Question

What is the C# equivalent of this geospatial T-SQL code?

DECLARE @g geography;
DECLARE @h geography;
SET @g = geography::STGeomFromText('POLYGON((-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))', 4326);
SET @h = geography::Point(47.653, -122.358, 4326)
SELECT @g.STIntersects(@h)

I am trying to find a point in a polygon using the SqlGeometry data type -- and can with the above T-SQL; but I do not understand how to achieve equivalent C# code.

• Damith: possible duplicate of Geo functions from SQL Server 2008 to C# (latitude and longitude points inside or outside polygon/map area)

Answer 1

Try this:

public bool OneOffSTIntersect()
{
 var g =
 Microsoft.SqlServer.Types.SqlGeography.STGeomFromText(
 new System.Data.SqlTypes.SqlChars(
 "POLYGON((-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))"), 4326);
 // suffix "d" on literals below optional but explicit
 var h = Microsoft.SqlServer.Types.SqlGeography.Point(47.653d, -122.358d, 4326);
 // rough equivalent to SELECT
 System.Console.WriteLine(g.STIntersects(h));
 // Alternatively return from a C# method or property (get).
 return g.STIntersects(h);
}

MSDN's SqlGeography Methods page links to info on each of the C# equivalents to the critical calls in your T-SQL - e.g. STIntersects.

• Tim: // rough equivalent to SELECT :-)
• J0e3gan: @Tim: Funny, last night this just came out the way I thought it not knowing the OP's general level of C# knowledge or context to use the translated code; but today this strikes me as pretty funny too. :) Thanks for pointing it out.