Public Class Form1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        Dim test() = {"was", "", "ist", "", "das", "?"}
        Dim temp As String = ""
        For i As Integer = 0 To test.Length - 1
            If test(i) <> "" Then
                temp += test(i)
            End If
        Next
        ListBox1.Items.Add(temp)
    End Sub
End Class