DataSource Controls :: Use Scope Identity To Get Newly Inserted Table

I have an SQL Server table named "Fields" with an autoincrement identity column "FieldID" as the primary key, an nchar column "Phrase" that textbox entries are to be stored in from a web page, and another column that is defaulted to null. The following is the recommended example on how to use Scope_Identity() to get a newly inserted table row identity value:

//C#
string query = "Insert Into Categories (CategoryName) Values (@CategoryName);" +
"Select Scope_Identity()";
int ID;
string connect = @"Server=.SQLExpress;AttachDbFilename=|DataDirectory|Northwind.mdf;" +
"Database=Northwind;Trusted_Connection=Yes;";
using (SqlConnection conn = new SqlConnection(connect))
{
using (SqlCommand cmd = new SqlCommand(query, conn))
{
cmd.Parameters.AddWithValue("@CategoryName", Category.Text);
conn.Open();
ID = (int)cmd.ExecuteScalar();
}
}

Obviously, this example uses a Categories Table in a Northwind database, which I do not have. So I am confused by how to adapt this example for my application. The following is my data context:

DataClassesDataContext db = new DataClassesDataContext();

Could you explain how I can adapt the example for my "Fields" table in my "EFMDB" database?