Private Sub MyListBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs)
        Dim ID as integer
        ID = MyListBox.SelectedValue

    End Sub

Dim strsql As String = "select Name where MyID=ID"

Imports System.Data.SqlClient
Imports System
Imports System.Data
Imports System.Windows.Forms



Public Class FrmTekeningen

    Dim strGeselecteerdeBedrijven As String = ""
    'Create a variable to hold your parameter value  
    Dim BedrID As Integer

    Private Sub TekeningenBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
        Me.Validate()
        Me.TekeningenBindingSource.EndEdit()
        Me.TekeningenTableAdapter.Update(Me.DocRegDataDataSet.Tekeningen)

    End Sub

    Private Sub BedrijvenIDListBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BedrijvenIDListBox.SelectedIndexChanged
        BedrID = BedrijvenIDListBox.SelectedValue

    End Sub


    Private Sub FrmTekeningen_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'DocRegDataDataSet.Bedrijven' table. You can move, or remove it, as needed.
        Me.BedrijvenTableAdapter.Fill(Me.DocRegDataDataSet.Bedrijven)
        'TODO: This line of code loads data into the 'DocRegDataDataSet.Tekeningen' table. You can move, or remove it, as needed.
        Me.TekeningenTableAdapter.Alle_Tekeningen(Me.DocRegDataDataSet.Tekeningen)

    End Sub

    Private Sub BtnBedrijven_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnBedrijven.Click
        Me.Visible = False
        My.Forms.Hoofdmenu.Show()

    End Sub

  

    Private Sub BtnTekeningenBedrijf_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnTekeningenBedrijf.Click
        'Create your query as you already have done  
        Dim strsql As String = "select bladnummer, naam, datum from tekeningen where BedrijvenID=@BedrijfID"
        'Get your connection string (You've done this right)  
        Dim strconnectionstring As String = My.Settings.DocRegDataConnectionString
        'Create your SqlConnection (Done)  
        Dim objconnection As New SqlConnection(strconnectionstring)
        'Create your SqlCommand (done)  
        Dim objcommand As New SqlCommand()

        '**Set your command properties**  
        With objcommand
            .CommandText = strsql
            .CommandType = CommandType.Text
            .Parameters.AddWithValue("@BedrijfID", BedrID)
            .Connection = objconnection
        End With
        'Create a new SqlDataAdapter  
        Dim objdataAdapter As New SqlDataAdapter()
        'Set the SelectCommand property of our adapter  
        objdataAdapter.SelectCommand = objcommand
        'Create a new DataSet  
        Dim objdataset As New DataSet
        'Fill the DataSet using the SqlDataAdapter  
        objdataAdapter.Fill(objdataset, "Tekeningenbedrijven")

        Dim objbindingsource As New BindingSource
        objbindingsource.DataSource = objdataset.Tables("Tekeningenbedrijven")

        TekeningenDataGridView.DataSource = objbindingsource
        objdataset.Clear()

    End Sub

End Class

BedrID = CType(BedrijvenIDListBox.SelectedItem(), Integer)