Dim lst As WinForm.ListBox = e.form.Controls("ListBox1")
Dim Count As Integer = DataTables("SFMX").Compute("Count(ZT)","DY = 0")
If Count > 0 Then
    Dim Arys As List(Of String())
    Arys = DataTables("SFMX").GetUniqueValues("", "BH","BRXM","MC")
    For Each Ary As String() In Arys
        lst.items.Add(ary(0) & "," & ary(1) & "," & ary(2))
    Next
End If

上面代码放在窗口按钮中，没按一次，就会生成重复的项目。如何在点击按钮后先清空ListBox中的项目items，然后再生成新的项目。