DUVIDA EM CODIGO VB.NET NA CLASSE SQLCOMMAND

DALTINHU 24/09/2012 01:28:00
#410310

Public Function InserirEmployee(ByVal emp As Employee) As Integer

Dim con As New SqlConnection(connectionString)
Dim cmd As New SqlCommand([Ô]InserirEmployee[Ô], con)

cmd.CommandType = CommandType.StoredProcedure




cmd.Parameters.Add(New SqlParameter([Ô]@FirstName[Ô], SqlDbType.NVarChar, 10))
cmd.Parameters([Ô]@FirstName[Ô]).Value = emp.FirstName
cmd.Parameters.Add(New SqlParameter([Ô]@LastName[Ô], SqlDbType.NVarChar, 20))
cmd.Parameters([Ô]@LastName[Ô]).Value = emp.LastName
cmd.Parameters.Add(New SqlParameter([Ô]@TitleOfCourtesy[Ô], SqlDbType.NVarChar, 25))
cmd.Parameters([Ô]@TitleOfCourtesy[Ô]).Value = emp.TitleOfCourtesy
cmd.Parameters.Add(New SqlParameter([Ô]@EmployeeID[Ô], SqlDbType.Int))
cmd.Parameters([Ô]@EmployeeID[Ô]).Direction = ParameterDirection.Output
Try
con.Open()
cmd.ExecuteNonQuery()
Return CInt(cmd.Parameters([Ô]@EmployeeID[Ô]).Value)
Catch err As SqlException
[ô] Substitui o erro com algo menos especifico
Throw New ApplicationException([Ô]Erro ao acessar os dados..[Ô])
Finally
con.Close()
End Try
End Function





Gostaria de saber pq usar isso:

cmd.Parameters.Add(New SqlParameter([Ô]@FirstName[Ô], SqlDbType.NVarChar, 10))

E nao isso:

cmd.Parameters.Add([Ô]@FirstName[Ô], SqlDbType.NVarChar, 10)


Se alguém que manja puder me explicar...