Public Function ExecuteNonQuery(sql As String, ByVal ParamArray para() As _
      KeyValuePair(Of String, Object)) As Int32
        Dim con As SqlConnection = GetConnection()
        Dim cmd As SqlCommand = con.CreateCommand()
        cmd.CommandText = sql
        For Each parameter As KeyValuePair(Of String, Object) In para
            cmd.Parameters.AddWithValue(parameter.Key, parameter.Value)
        Next
        cmd.Transaction = _Transaction 
        Return cmd.ExecuteNonQuery()
    End Function
    Public Function ExecuteScalar(sql As String, ByVal ParamArray para() As _
      KeyValuePair(Of String, Object)) As Object
        Dim con As SqlConnection = GetConnection()
        Dim cmd As SqlCommand = con.CreateCommand()
        cmd.CommandText = sql
        For Each parameter As KeyValuePair(Of String, Object) In para
            cmd.Parameters.AddWithValue(parameter.Key, parameter.Value)
        Next
        cmd.Transaction = _Transaction 
        Return cmd.ExecuteScalar()
    End Function