Insert and delete in sql datbase and gridvew

using (SqlConnection con = new SqlConnection(strConnect))
    {
    con.Open();
    using (SqlCommand com = new SqlCommand("INSERT INTO myTable (myColumn1, myColumn2) VALUES (@C1, @C2)", con))
        {
        com.Parameters.AddWithValue("@C1", myValueForColumn1);
        com.Parameters.AddWithValue("@C2", myValueForColumn2);
        com.ExecuteNonQuery();
        }
    }

using (SqlConnection con = new SqlConnection(strConnect))
    {
    con.Open();
    using (SqlCommand com = new SqlCommand("UPDATE myTable SET myColumn1=@C1, myColumn2=@C2 WHERE Id=@ID", con))
        {
        com.Parameters.AddWithValue("@ID", id);
        com.Parameters.AddWithValue("@C1", myValueForColumn1);
        com.Parameters.AddWithValue("@C2", myValueForColumn2);
        com.ExecuteNonQuery();
        }
    }