Imports System.Data.SqlClient
Imports System.Reflection

Public Class Class1

    Public sAppPath As String = Application.StartupPath
    'Public Shared DBConString As String = "Server=NBMIESENBECK\SPIELWIESE;Initial Catalog=Doku;User ID=sa;Password=verag#3;Connection Timeout=5;"
    Public Shared DBConString As String
    Public Shared DBConstringDev As String = "Server=DEVELOPER.verag.ost.dmn\DEVSQL;Initial Catalog=Doku;User ID=sa;Password=BmWr501956;Connection Timeout=5;"
    Public Shared DBADMINBuchhaltung As String = "Data Source=192.168.0.94\SQLEXPRESS;Initial Catalog=ADMIN;Integrated Security=false;User ID=sa;Password=BmWr501956;"
    'Public Shared FilePath As String = "\\192.168.0.253\backup\temp_Sebastian\Spielwiese\Doku"
    Public Shared FilePath As String ' = "\\192.168.0.90\f\EDV-Wartung\Dokumentation"
    Public Shared Absender As String = "Absender Standard"
    'Public Shared sAppPath As String = Application.StartupPath
    Public Shared Standorte As New List(Of String)
    Public Shared AlleStandorte As New List(Of String)
    Public Shared LoggedOnUser As New cBenutzer
    Public Shared LoggedOnUserRights As New List(Of cBerechtigungen)
    Public Shared DebugMode As Boolean = False
    Public Shared GroupUsers As List(Of cBenutzer)

    Public Shared Sub EnableDoubleBuffered(ByVal dgv As DataGridView)
        Dim dgvType As Type = dgv.[GetType]()
        Dim pi As PropertyInfo = dgvType.GetProperty("DoubleBuffered",
                                                     BindingFlags.Instance Or BindingFlags.NonPublic)
        pi.SetValue(dgv, True, Nothing)
    End Sub

    Public Shared Function CheckDebug()
        Dim Startparameter As String = ""
        Dim i As Integer
        For Each s As String In Environment.GetCommandLineArgs
            If i > 0 Then
                If s = "/d" Or s = "-d" Then
                    Startparameter = "debug"
                Else
                End If
            End If
            i += 1
        Next

        If Main.sAppPath Like "*\bin\Debug" Or Startparameter = "debug" Then
            DebugMode = True

            Class1.DBConString = "Server=DEVELOPER\DEVSQL;Initial Catalog=Doku;User ID=sa;Password=BmWr501956;Connection Timeout=5;"
            Class1.FilePath = "\\192.168.0.253\backup\temp_Sebastian\DokuTest"
        Else
            Class1.DBConString = "Server=192.168.0.94\SQLEXPRESS;Initial Catalog=Doku;User ID=sa;Password=BmWr501956;Connection Timeout=5;"
            Class1.FilePath = "\\192.168.0.90\f\EDV-Wartung\Dokumentation"
        End If
    End Function



    Public Shared Function SQLnQ(command As String)

        Dim con As New SqlConnection
        Dim cmd As New SqlCommand

        con.ConnectionString = DBConString
        Try
            con.Open()
            cmd.Connection = con
            cmd.CommandText = command
            cmd.ExecuteNonQuery()
            con.Close()
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try
    End Function

    Public Shared Function dbload()

        Dim con As New SqlConnection
        Dim cmd As New SqlCommand


        con.ConnectionString = DBConString
        cmd.Connection = con
    End Function

    Public Shared Function csvexport(quelldgv As DataGridView)
        Dim savefiledialog As New SaveFileDialog
        Dim firstin As String
        Dim out As String
        Dim in2 As String
        Dim header As String

        savefiledialog.Filter = "CSV files (*.csv)|*.CSV"
        savefiledialog.InitialDirectory = "C:\Verag"
        savefiledialog.ShowDialog()


        Try
            For r As Integer = 0 To quelldgv.Rows.Count - 1
                For c As Integer = 0 To quelldgv.Columns.Count
                    'test &= r & c & vbCrLf
                    Try
                        'test &= Replace(quelldgv.Rows(r).Cells(c).Value.ToString, vbCrLf, "vbCrlLf")
                        firstin = quelldgv.Rows(r).Cells(c).Value.ToString
                        'in2 = """" & firstin & """" & ";"
                        in2 = firstin & ";"
                        out &= Replace(in2, vbCrLf, "##vbCrLf##")
                    Catch ex As Exception
                        out &= ""
                    End Try

                Next

                out &= "nZ"
            Next
            For c As Integer = 0 To quelldgv.Columns.Count - 1
                header &= quelldgv.Columns(c).Name & ";"
            Next
            out = Replace(out, "nZ", vbCrLf)
            'MsgBox(out)
            Using sw As New IO.StreamWriter(savefiledialog.FileName)
                sw.WriteLine(header)
                sw.WriteLine(out)
            End Using
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Function

    Public Shared Function hochkomma(textin As String)
        Dim textout As String = textin.Replace("'", "''")
        Return (textout)
    End Function

    Public Shared Function ip2netname(IP As String, ByRef NWStandort As String, ByRef netname As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        Dim NWAddress As String
        Dim pointcounter As Integer = 0
        Dim digcounter As Integer = 0

        con.ConnectionString = DBConString
        cmd.Connection = con

        For Each c As Char In IP
            If c = "." Then
                pointcounter = pointcounter + 1
            End If
            digcounter = digcounter + 1
        Next

        If pointcounter < 3 Or digcounter < 7 Then
            MsgBox("Das scheint keine gültige IP Adresse zu sein...")
            Exit Function
        End If

        NWAddress = IP.Substring(0, IP.LastIndexOf(".")) & "."

        con.Open()
        cmd.CommandText = "SELECT * FROM Tbl_Netzwerke WHERE NWAddress = '" & NWAddress & "' "
        cmd.ExecuteNonQuery()

        reader = cmd.ExecuteReader()
        Do While reader.Read
            NWStandort = reader("NWStandort")
            netname = reader("Netname")
        Loop
        reader.Close()
        con.Close()
    End Function

    Public Shared Function IPexist(IP As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = DBConString
        cmd.Connection = con

        con.Open()
        cmd.CommandText = "SELECT * FROM Tbl_Netzwerkclients WHERE IPAdresse = '" & IP & "'"
        cmd.ExecuteNonQuery()
        reader = cmd.ExecuteReader()
        If reader.Read Then
            MsgBox("Die IP Adresse " & IP & " ist bereits belegt!")
            Return True
            con.Close()
            Exit Function
        End If
        Return False
    End Function

    Public Shared Function IP2Host(IP As String)
        Dim pointcounter As Integer = 0
        Try
            Do
                If IP.StartsWith(".") Then
                    pointcounter = pointcounter + 1
                End If
                IP = IP.Remove(0, 1)

            Loop Until pointcounter = 3 'IP.First() = "."

            Return IP
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Function

    Public Shared Function ip2ipnet(ip As String)
        Dim lastbutnotleast As String = "."

        Do
            ip = ip.Remove((ip.Length - 1), 1)
        Loop Until ip.EndsWith(".")

        Return ip
    End Function

    Public Shared Function netmaskseperator(nm As String, ByRef a As Integer, ByRef b As Integer, ByRef c As Integer, ByRef d As Integer, ByRef nwbits As Integer, ByRef hostbits As Integer)
        Dim bitstring As String
        Try
            Do
                a &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                b &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                c &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                d &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.Length = 0

        Catch ex As Exception
            MsgBox("netmaskseperator: " & ex.Message)
        End Try
        Dim ai As Integer = Convert.ToString(a, 2)
        Dim bi As Integer = Convert.ToString(b, 2)
        Dim ci As Integer = Convert.ToString(c, 2)
        Dim di As Integer = Convert.ToString(d, 2)

        bitstring = ai & bi & ci & di
        nwbits = 0
        hostbits = 32
        For Each ch As Char In bitstring
            If ch = "1" Then
                nwbits = nwbits + 1
                hostbits = hostbits - 1
            End If
        Next

    End Function

    Public Shared Function mask2nwbit(nm As String, ByRef nwbits As Integer)
        Dim bitstring As String
        Dim a, b, c, d, hostbits As Integer
        Try
            Do
                a &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                b &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                c &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.First() = "."
            nm = nm.Remove(0, 1)
            Do
                d &= nm.Substring(0, 1)
                nm = nm.Remove(0, 1)
            Loop Until nm.Length = 0

        Catch ex As Exception
            MsgBox("netmaskseperator: " & ex.Message)
        End Try
        Dim ai As Integer = Convert.ToString(a, 2)
        Dim bi As Integer = Convert.ToString(b, 2)
        Dim ci As Integer = Convert.ToString(c, 2)
        Dim di As Integer = Convert.ToString(d, 2)

        bitstring = ai & bi & ci & di
        nwbits = 0
        hostbits = 32
        For Each ch As Char In bitstring
            If ch = "1" Then
                nwbits = nwbits + 1
                hostbits = hostbits - 1
            End If
        Next

    End Function

    Public Shared Function bit2mask(bit As String, ByRef mask As String)
        Dim a, b, c, d As String

        If bit \ 8 >= 1 Then
            a = "255"
            bit = bit - 8
            If bit \ 8 >= 1 Then
                b = "255"
                bit = bit - 8
                If bit \ 8 >= 1 Then
                    c = "255"
                    bit = bit - 8
                    If bit \ 8 >= 1 Then
                        d = "255"
                        bit = bit - 8
                    Else
                        d = 256 - (2 ^ (8 - bit))
                    End If
                Else
                    c = 256 - (2 ^ (8 - bit))
                    d = 0
                End If
            Else
                b = 256 - (2 ^ (8 - bit))
                c = 0
                d = 0
            End If
        Else
            a = 256 - (2 ^ (8 - bit))
            b = 0
            c = 0
            d = 0
        End If

        mask = a & "." & b & "." & c & "." & d
        Return mask
    End Function

    Private Shared Function checknull(text As String)
        Dim Reader As SqlDataReader
        Try
            ' If reader.Read() Then
            If Reader.IsDBNull(0) Then
                'MsgBox("Null")
                Return String.Empty
            Else
                Return Reader(text).ToString
            End If
            'End If
        Catch ex As Exception
            'MsgBox("Checknull: " & ex.Message)
        End Try
    End Function

    Public Shared Function NWAddressGenerieren(NWAddress As String, ByRef IPShort As String)
        Try
            Do
                NWAddress = NWAddress.Remove(NWAddress.Length - 1)

            Loop Until NWAddress.Last() = "."
        Catch ex As Exception
            MsgBox("Fehler beim Konvertieren der Netzwerkadresse.")
        End Try
        IPShort = NWAddress
    End Function

    Public Shared Function getStartEndHost(ByVal ip As String, ByRef starthost As Integer, ByRef endhost As Integer)
        Dim Standort, Name, subnetmask As String
        Dim nwbits As Integer
        Dim nwad As String = IP2ShortNW(ip)
        NetzwerkadresseInfo(nwad, Standort, Name, subnetmask)
        mask2nwbit(subnetmask, nwbits)
        Dim Hostbits As Integer = 32 - nwbits
        Dim AnzahlHosts As Integer = (2 ^ Hostbits) - 2
        starthost = IP2Host(nwad) + 1
        endhost = starthost + (AnzahlHosts - 1)
    End Function

    Public Shared Function Netzwerkfuellen(NWAdresse As String, NWBits As Integer, Netname As String, NWStandort As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = DBConString
        cmd.Connection = con
        Dim AnzahlHosts As Integer
        Dim Hostbits As Integer = 32 - NWBits
        AnzahlHosts = (2 ^ Hostbits) - 2
        Dim Starthost As Integer = IP2Host(NWAdresse) + 1
        Dim IPShort As String
        NWAddressGenerieren(NWAdresse, IPShort)
        ' Dim NWStandort, NetName As String
        'ip2netname(NWAdresse, NWStandort, NetName)

        For Host As Integer = Starthost To (Starthost + AnzahlHosts - 1)
            Dim IP As String = IPShort & Host
            con.Open()
            cmd.CommandText = "Select FQDN, Modell FROM Tbl_Netzwerkclients WHERE IPAdresse = '" & IP & "' "
            reader = cmd.ExecuteReader()
            Try
                reader.Read()
                reader.IsDBNull(0)
                'Label2.Text &= "Try" & IP & vbCrLf
            Catch
                'MsgBox("Catch")
                con.Close()
                con.Open()
                cmd.CommandText = "INSERT INTO Tbl_Netzwerkclients (IPAdresse, HOST, Netname, NWStandort, Linked, Netzwerk, LinkedWith) VALUES ('" & IP & "', '" & Host & "','" & Netname & "','" & NWStandort & "', '0', '" & NWAdresse & "', '')"
                cmd.ExecuteNonQuery()
                con.Close()
                'Label2.Text &= "Catch" & cmd.CommandText & IP & vbCrLf
            End Try
            con.Close()
            con.Open()
            cmd.CommandText = "UPDATE Tbl_Netzwerkclients SET NETZWERK='" & NWAdresse & "' WHERE NETNAME = '" & Netname & "' AND NWStandort = '" & NWStandort & "'"
            cmd.ExecuteNonQuery()
            con.Close()
        Next

    End Function

    Public Shared Function NetzwerkadresseInfo(Netzwerkadresse As String, ByRef Standort As String, ByRef Name As String, ByRef subnetmask As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = DBConString
        cmd.Connection = con

        con.Open()
        cmd.CommandText = "SELECT * FROM Tbl_Netzwerke WHERE NETZWERK = '" & Netzwerkadresse & "'"
        reader = cmd.ExecuteReader()
        Do While reader.Read
            Standort = reader("NWSTANDORT")
            Name = reader("NETNAME")
            subnetmask = reader("Subnetz")
        Loop
        reader.Close()
        con.Close()
    End Function

    Public Shared Function getDHCPstartend(Netzwerkadresse As String, ByRef DHCPStart As String, ByRef DHCPEnd As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = DBConString
        cmd.Connection = con

        Try
            con.Open()
            cmd.CommandText = "SELECT * FROM Tbl_Netzwerke WHERE NETZWERK = '" & Netzwerkadresse & "'"
            reader = cmd.ExecuteReader()
            Do While reader.Read
                DHCPStart = reader("DHCPStart")
                DHCPEnd = reader("DHCPEnd")
                'subnetmask = reader("Subnetz")
            Loop
            reader.Close()
            con.Close()
        Catch
            DHCPStart = 0
            DHCPEnd = 0
        End Try

    End Function

    Public Shared Function DHCPFill(dhcpstart As String, dhcpend As String, nw As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = DBConString
        cmd.Connection = con

        Try
            dhcpstart = Convert.ToInt32(dhcpstart)
            dhcpend = Convert.ToInt32(dhcpend)
        Catch ex As Exception
            dhcpstart = 0
            dhcpend = 0
            'LblInfo.Text = "DHCP nicht anwendbar"
            'Exit Function
        End Try
        If dhcpstart < 1 Or dhcpend > 254 Then
            'MsgBox("der DHCP Bereich kann nicht stimmen...")
            'Exit Function
        End If
        con.Open()
        cmd.CommandText = "select IPadresse, DHCP from TbL_Netzwerkclients Where NETNAME = (select NETNAME from TbL_Netzwerke Where Netzwerk = '" & nw & "') AND NWSTANDORT = (select NWSTANDORT from TbL_Netzwerke Where Netzwerk = '" & nw & "') ORDER BY HOST"
        reader = cmd.ExecuteReader()

        Do While reader.Read()
            Dim IPAdresse As String = reader("IPAdresse")
            Dim Host As Integer = Class1.IP2Host(IPAdresse)

            If Host = dhcpstart Then
                DHCPUpdate("Start", IPAdresse)
            ElseIf Host = dhcpend Then
                DHCPUpdate("Ende", IPAdresse)
            ElseIf Host > dhcpstart And Host < dhcpend Then
                DHCPUpdate("1", IPAdresse)
            Else
                DHCPUpdate("0", IPAdresse)
            End If
        Loop
        reader.Close()
        con.Close()
        '  LblInfo.Text = "Gespeichert."
        ' Timer3.Enabled = True
    End Function

    Public Shared Function DHCPUpdate(Wert As String, IPAdresse As String)
        Dim dhcpcon As New SqlConnection
        Dim dhcpcmd As New SqlCommand
        dhcpcon.ConnectionString = Class1.DBConString
        dhcpcmd.Connection = dhcpcon

        dhcpcon.Open()
        dhcpcmd.CommandText = "UPDATE TbL_Netzwerkclients SET DHCP = '" & Wert & "' WHERE IPAdresse = '" & IPAdresse & "'"
        dhcpcmd.ExecuteNonQuery()
        dhcpcon.Close()
    End Function


    Public Shared Function RefillNW(netzwerk As String)
        Dim NWStandort, NWName, Subnet, dhcpstart, dhcpend As String
        Dim NWBits As Integer

        Class1.NetzwerkadresseInfo(netzwerk, NWStandort, NWName, Subnet)
        Class1.mask2nwbit(Subnet, NWBits)
        Class1.Netzwerkfuellen(netzwerk, NWBits, NWName, NWStandort)
        Class1.getDHCPstartend(netzwerk, dhcpstart, dhcpend)
        Class1.DHCPFill(dhcpstart, dhcpend, netzwerk)
    End Function

    Public Shared Function GetFQDNandType(IPAdresse As String, ByRef FQDN As String, ByRef Type As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con


        con.Open()
        cmd.CommandText = "SELECT * FROM TbL_Netzwerkclients WHERE IPAdresse = '" & IPAdresse & "'"
        reader = cmd.ExecuteReader()
        Do While reader.Read
            FQDN = ReadNullAsEmptyString(reader, "FQDN")
            Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()
    End Function

    Public Shared Function ReadNullAsEmptyString(ByVal reader As IDataReader, ByVal Abfrage As String)
        If IsDBNull(reader(Abfrage)) Then
            Return ""
        Else
            Return reader(Abfrage)
        End If
    End Function
    Public Shared Function ReadNullAs0(ByVal reader As IDataReader, ByVal Abfrage As String)
        If IsDBNull(reader(Abfrage)) Then
            Return "0"
        Else
            Return reader(Abfrage)
        End If
    End Function

    Public Shared Function Host2IP(ByVal Host As String, ByVal nwstandort As String, ByVal netname As String, ByRef IP As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con


        con.Open()
        cmd.CommandText = "SELECT * FROM TbL_Netzwerkclients WHERE HOST = '" & Host & "' AND NWStandort = '" & nwstandort & "' AND NETNAME = '" & netname & "'"
        reader = cmd.ExecuteReader()
        Do While reader.Read
            IP = ReadNullAsEmptyString(reader, "IPAdresse")
            'Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()

    End Function

    Public Shared Function Name2Netzwerk(ByVal nwstandort As String, ByVal netname As String, ByRef Netzwerk As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con


        con.Open()
        cmd.CommandText = "SELECT Netzwerk FROM TbL_Netzwerke WHERE NWStandort = '" & nwstandort & "' AND NETNAME = '" & netname & "'"
        reader = cmd.ExecuteReader()
        Do While reader.Read
            Netzwerk = ReadNullAsEmptyString(reader, "Netzwerk")
            'Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()

    End Function
    Public Shared Function IP2ShortNW(ByVal IPAdresse As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con
        Dim Netzwerk As String


        con.Open()
        cmd.CommandText = "SELECT Netzwerk FROM TbL_Netzwerkclients WHERE IPAdresse = '" & IPAdresse & "' "
        reader = cmd.ExecuteReader()
        Do While reader.Read
            Netzwerk = ReadNullAsEmptyString(reader, "Netzwerk")
            'Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()
        Return Netzwerk
    End Function

    Public Shared Function GetDHCPServer(ByVal Netzwerkadresse As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con
        Dim DHCPServer As String


        con.Open()
        cmd.CommandText = "SELECT DHCPServer FROM TbL_Netzwerke WHERE Netzwerk = '" & Netzwerkadresse & "' "
        reader = cmd.ExecuteReader()
        Do While reader.Read
            DHCPServer = ReadNullAsEmptyString(reader, "DHCPServer")
            'Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()
        Return DHCPServer
    End Function

    Public Shared Function Autocomplete(ByRef txtbox As TextBox, spalte As String, Tabelle As String)
        Dim tmp As New AutoCompleteStringCollection()
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con

        Try
            con.Open()

            Dim ds As New DataSet()
            Dim dt As New DataTable()
            Dim dataadapter As New SqlDataAdapter("SELECT Distinct " & spalte & " from " & Tabelle & "", con)
            dataadapter.Fill(ds)

            '  txtbox.AutoCompleteMode = AutoCompleteMode.SuggestAppend
            ' txtbox.AutoCompleteSource = AutoCompleteSource.CustomSource
            txtbox.AutoCompleteCustomSource = tmp

            For Each dr As DataRow In ds.Tables(0).Rows
                Try
                    tmp.Add(dr.Item(0))
                Catch
                End Try

                'Items.Add(dr.Item(0))
            Next

            con.Close()
        Catch ex As Exception
            MsgBox("Fehler Autocomplete: " & ex.Message)
            con.Close()
        End Try
        con.Close()
    End Function

    Public Shared Function GetUserPasswort(ip As String, ByRef User As String, ByRef Password As String)
        Dim tmp As New AutoCompleteStringCollection()
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con

        con.Open()
        cmd.CommandText = "SELECT Benutzer, Passwort FROM TbL_Netzwerkclients WHERE IPAdresse = '" & ip & "' "
        reader = cmd.ExecuteReader()
            Do While reader.Read
            User = ReadNullAsEmptyString(reader, "Benutzer")
            Password = ReadNullAsEmptyString(reader, "Passwort")
        Loop
            con.Close()


    End Function

    Public Shared Function MainHost(ip As String)
        Dim tmp As New AutoCompleteStringCollection()
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con

        Dim LinkedWith As String

        con.Open()
        cmd.CommandText = "SELECT LinkedWith FROM TbL_Netzwerkclients WHERE IPAdresse = '" & ip & "' "
        reader = cmd.ExecuteReader()
        Do While reader.Read
            LinkedWith = ReadNullAsEmptyString(reader, "LinkedWith")
        Loop
        con.Close()

        If LinkedWith = "" Then
            Return ip
        Else
            Return LinkedWith
        End If

    End Function

    Public Shared Function IsLinked(ByVal IPAdresse As String)
        Dim con As New SqlConnection
        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader
        con.ConnectionString = Class1.DBConString
        cmd.Connection = con
        Dim Linked As String


        con.Open()
        cmd.CommandText = "SELECT Linked FROM TbL_Netzwerkclients WHERE IPAdresse = '" & IPAdresse & "' "
        reader = cmd.ExecuteReader()
        Do While reader.Read
            Linked = ReadNullAsEmptyString(reader, "Linked")
            'Type = ReadNullAsEmptyString(reader, "Type")
        Loop
        con.Close()
        Return Linked
    End Function

    Public Shared Function DBNull2emptyString(totest As Object)

        If IsDBNull(totest) Then
            Return ""
        Else
            Return totest
        End If

    End Function

    Public Shared Function OrderDataTableby(dt As DataTable, orderby As String)
        Dim dv As New DataView(dt)

        dv.Sort = orderby
        Dim returnTable As DataTable = dv.ToTable
        'returnTable = dv.Table
        Return returnTable
    End Function
End Class