使用SqlHelper的一个小技巧(2)

''' <param name="commandParameters">an array of SqlParameters to be associated with the command or 'null' if no parameters are required</param>
Private Shared Sub PrepareCommand(ByVal command As SqlCommand, _
                                    ByVal connection As SqlConnection, _
                                    ByVal transaction As SqlTransaction, _
                                    ByVal commandType As CommandType, _
                                    ByVal commandText As String, _
                                    ByVal commandParameters() As SqlParameter)

    'if the provided connection is not open, we will open it
    If connection.State <> ConnectionState.Open Then
        connection.Open()
    End If

    'associate the connection with the command
    command.Connection = connection

    'set the command text (stored procedure name or SQL statement)
    command.CommandText = commandText

    'if we were provided a transaction, assign it.
    If Not (transaction Is Nothing) Then
        command.Transaction = transaction
    End If

    'set the command type
    command.CommandType = commandType

    'attach the command parameters if they are provided
    If Not (commandParameters Is Nothing) Then
        For Each p As SqlParameter In commandParameters
            If (p.Direction <> ParameterDirection.Output) Then
                Select Case p.DbType
                    Case DbType.String, DbType.StringFixedLength, DbType.AnsiString, DbType.AnsiStringFixedLength