将参数发送到存储过程vb.net

Question

您好,这是我在vb.net中使用ms visual studio 2010的第一个项目,我想创建一个可以将参数发送到transact-sql数据库中的存储过程的类,我知道如何在vb 6中执行它,但我不是确定这是否是在这里做到的正确方法.

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

我的一些疑虑是:

每次调用我班级的方法时,我真的需要打开数据库吗？

是否真的需要sqlAdapter和Dataset？在vb 6中,您可以在附加参数后执行类似"命令执行插入"的操作,以及完成的位置.

Answer 1

如果您只是读取数据,请检查SqlDataReader:

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

如果您正在进行更新或插入,那么您可以使用SqlCommand类的ExecuteNonQuery()方法.

SqlCommand有一个添加参数的简写:

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

您可能觉得有用.

是的,每次需要与数据库交互时,都应该打开和关闭数据库连接.阅读Using语句,它将帮助您做得很好,整洁.