Imports System.IO

Public Class Form1

    Private Sub btnExportar_Click(sender As Object, e As EventArgs) Handles btnExportar.Click
        Dim desde As Date = dtpDesde.Value
        Dim hasta As Date = dtpHasta.Value

        Dim dtGenerarTxt As DataTable = fGenerarTxt(desde, hasta)


        MessageBox.Show(String.Format("Desde: {0}, Hasta {1}", desde, hasta))
    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        dtpDesde.MinDate = New Date(2003, 1, 1)
        dtpDesde.MaxDate = Date.Now
    End Sub

    Public Function fGenerarTxt(ByVal vDesde As Date, ByVal vHasta As Date) As DataTable
        'Dim cCapaDatos As clsCapaDatos = New clsCapaDatos
        Dim dtTable As DataTable = New DataTable
        'Try
        '    cCapaDatos.sConectarSQL()
        '    Dim sTextoSQL As String = "Tesoreria.obd_conusltar_ruc"
        '    cCapaDatos.sComandoSQL(sTextoSQL, CommandType.StoredProcedure)
        '    cCapaDatos.sParametroSQL("@min_date", DbType.Date, 10, vDesde)
        '    cCapaDatos.sParametroSQL("@max_date", DbType.Date, 10, vHasta)
        '    cCapaDatos.sAdaptadorSQL("R")
        '    dtTable = cCapaDatos.fListarTabla()
        '    Dim iNroRegistros As Integer = Convert.ToInt32(cCapaDatos.fListarTabla.DefaultView.Count)
        'Catch ex As Exception
        '    cTempo.sMensaje(Convert.ToString(ex.Message))
        'Finally
        '    cCapaDatos.sDesconectarSQL()
        'End Try
        Return dtTable
    End Function

    Private Sub ExportarArchivos(ByVal dtGenerarTxt As DataTable)
        Dim cad As String = ""

        Dim maxRows As Integer = 100
        Dim contador As Integer
        Dim numArchivo As Integer = 1
        Dim ruta As String = "C:/ususario/carpeta/"

        If dtGenerarTxt.Rows.Count > 0 Then
            For i As Integer = 0 To dtGenerarTxt.Rows.Count - 1
                contador = contador + 1
                cad += dtGenerarTxt.Rows(i)("RUC").ToString & "|" & vbNewLine

                If contador = maxRows Or i = dtGenerarTxt.Rows.Count - 1 Then
                    numArchivo += 1
                    File.WriteAllText(ruta & "ruc_proveedor_" & dtGenerarTxt.Rows(0)("PERIODO").ToString & "_" & numArchivo & ".txt", cad)
                    contador = 0
                End If
            Next

            MessageBox.Show("Se generó correctamente el archivo. ", Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Information)
        End If
    End Sub

End Class