Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button3.Click
 
        Dim jahr As Integer = CInt(Me.ComboBox1.Text + Me.TextBox1.Text)
        Dim Filter As String
        Filter = Me.ComboBox1.Text + " LIKE '" + Me.TextBox1.Text + "'"
        DV1.RowFilter = "Geburtsdatum>=#01/01/" & CStr(jahr) & "# And" & _
          "Geburtsdatum<#01/01/" & CStr(jahr + 1) & "#"
        DV1.RowFilter = Filter
 
    End Sub

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