SqlDbType and Geography

Question

What SqlDbType enumeration should I use when my column is the Geography type? I\'m using MS SQL Server 2008 R2.

This is what I\'m looking for specifically:

Answer 1

SqlGeography is implemented as a CLR user defined type by SQL Server, so you can do something a little like:

SqlGeography geo = // Get the geography from somewhere...

using (SqlCommand command = 
    new SqlCommand(@"dbo.up_Foobar_Insert", connection))
    command.Parameters.Add(new SqlParameter("@Point", geo) { UdtTypeName = "Geography" });
    command.ExecuteNonQuery();
}

If it is a desktop application you've got it quite a bit easier. There is a good example at the Code Project of an SQL Geometry viewer that will help for both desktop or web.

You need to reference Microsoft.SqlServer.Types.dll, found at SQL Server Install/100/SDK/Assemblies to use SQLGeometry or SQLGeography directly.

Answer 2

Update

Try this:

//define parameter
command.Parameters.Add("@shape", SqlDbType.NVarChar);
//
//code in between omitted
//
//set value of parameter
command.Parameters["@shape"].Value = feature.Geometry.AsText();

Taken from Inserting SQL 2008 Geometry With a SqlCommand

Answer 3

When I tried to use SqlDbType.NVarChar I received and error

Failed to convert parameter value from Geography to a String

What resolved this problem for me was to use SqlDbType.Udt

var pgeo = cmd.Parameters.Add("@GeoLocation", SqlDbType.Udt);
pgeo.UdtTypeName = "Geography";

And then later, in a loop, I set the value of the parameter:

var ss = new SqlString(objValue.ToString());
var sc = new SqlChars(ss);
var geocode = SqlGeography.STPointFromText(sc, 4326);
cmd.Parameters["@GeoLocation"].Value = geocode;

Note: this requires Microsoft.SqlServer.Types and System.Data.SqlTypes