cargar un combobox con datos sql

Private Sub folios_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim con As New SqlConnection(Form1.conex)
        Dim query As String = "select rut_empresa from empresas"
        con.Open()
        Using cmd As New SqlCommand(query, con)
            Dim rs As SqlDataReader = cmd.ExecuteReader
            While rs.Read
                cbRutEmpresas.Items.Add(rs("rut_empresa").ToString)
            End While
            rs.Close()

        End Using
        con.Close()
    End Sub


Private Sub folios_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim con As New SqlConnection(Form1.conex)
        Dim query As String = "select rut_empresa from empresas"
        con.Open()
        Using cmd As New SqlCommand(query, con)

            Dim adapter As New SqlDataAdapter(cmd)
            Dim table As New DataTable()
            adapter.Fill(table)
            cbRutEmpresas.DataSource = table
            cbRutEmpresas.DisplayMember = "id" ' columna id de la tabla empresas
            cbRutEmpresas.ValueMember = "rut_empresa" ' columna rut_empresa de la tabla rut_empresa
        End Using
        con.Close()
    End Sub


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Leer tabla sql

Dim query As String = "SELECT * FROM tabla"
        Try
            Dim con As New SqlConnection(conex)
            con.Open()
            Dim cmd As New SqlCommand(query, con)
            Dim dr As SqlDataReader = cmd.ExecuteReader()
            While dr.Read
                Dim id As String = dr.GetValue(0).ToString.Trim
                Dim name As String = dr.GetValue(1).ToString.Trim
                Dim code As String = dr.GetValue(2).ToString.Trim
                
            End While
            dr.Close()
            con.Close()
        Catch ex As Exception
        End Try