Sending parameters to stored procedures vb.net

Question

Hello this my first project in vb.net working with ms visual studio 2010, i want to create a class that can send parameters to stored procedures in an transact-sql database, i know how to do it in vb 6 but i'm not sure if this the right way to do it in here.

Imports System.Data.SqlClient

Public Class ClsLineas

Public Sub Inserta(ByVal GridLineas As DataGrid, _
                   ByVal numero As String, _
                   ByVal tipo As String, _
                   ByVal estado As String, _
                   ByVal anexo As Integer, _
                   ByVal fechaInicio As String, _
                   ByVal fechaFin As String, _
                   ByVal pcReg As String, _
                   ByVal observaciones As String, _
                   ByVal usuReg As String)

    Dim cnx As SqlConnection = New SqlConnection(ClsCon.connectionString)
    'ClsCon.connectionString is a class that contains the connection string 
    Dim cmd As SqlCommand = New SqlCommand()

    If cnx.State = ConnectionState.Closed Then cnx.Open()

    cmd.Connection = cnx
    cmd.CommandText = "SP_INSERTA_LINEA"
    cmd.CommandType = CommandType.StoredProcedure

    Dim prm As New SqlParameter

    prm.ParameterName = "@TIPO"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 30
    prm.Direction = ParameterDirection.Input
    prm.Value = tipo
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@FECHA_INICIO"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 30
    prm.Direction = ParameterDirection.Input
    prm.Value = fechaInicio
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@FECHA_FIN"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 30
    prm.Direction = ParameterDirection.Input
    prm.Value = fechaFin
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@ESTADO"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 30
    prm.Direction = ParameterDirection.Input
    prm.Value = estado
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@NUMERO"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 15
    prm.Direction = ParameterDirection.Input
    prm.Value = numero
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@ANEXO"
    prm.SqlDbType = SqlDbType.Int
    prm.Direction = ParameterDirection.Input
    prm.Value = anexo
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@PC_REG"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 50
    prm.Direction = ParameterDirection.Input
    prm.Value = pcReg
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@USU_REG"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 50
    prm.Direction = ParameterDirection.Input
    prm.Value = usuReg
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@OBSERVACIONES"
    prm.SqlDbType = SqlDbType.NVarChar
    prm.Size = 1000
    prm.Direction = ParameterDirection.Input
    prm.Value = observaciones
    cmd.Parameters.Add(prm)

    prm.ParameterName = "@ID"
    prm.SqlDbType = SqlDbType.Int
    prm.Direction = ParameterDirection.Output
    cmd.Parameters.Add(prm)

    Dim adp As SqlDataAdapter = New SqlDataAdapter(cmd)

    Dim DataSet As DataSet = New DataSet("Lineas")

    adp.Fill(DataSet)
    GridLineas.DataSource = DataSet.Tables(0)

End Sub
End class

Some of my doubts are:

Do i really need to open the database every time i call the methods of my class?

Are the sqlAdapter and Dataset really needed? In vb 6 you could do something like "command execute inserta" after appending the parameters and you where done.

Answer 1

If you're just reading data then checkout the SqlDataReader:

Dim reader As SqlDataReader
reader = cmd.ExecuteReader()
While reader.Read
    //Do stuff with reader
End While

If you are doing an update or an insert then you can use the ExecuteNonQuery() method of the SqlCommand class.

SqlCommand has a shorthand for adding parameters:

cmd.Parameters.AddWithValue("@MyParamName", myParamValue)

Which you may find useful.

And yes you should open and close a database connection every time you need to interact with the database. Read up on the Using statement, which will help you to do this nice and neatly.