主题：CheckedListBox求助

systemready = False
If e.Sender.SelectedValue = "全部"
    For i As Integer = 0 To e.Sender.Items.Count - 1
        e.Sender.SetItemChecked(i, e.Checked)
    Next
End If

If e.Sender.SelectedValue = "非空"
    For i As Integer = 0 To e.Sender.Items.Count - 1
        If e.sender.Items(i) <> "全部" AndAlso e.sender.Items(i) <> "空值" Then
            e.Sender.SetItemChecked(i, e.Checked)
        Else
            e.Sender.SetItemChecked(i, False)
        End If
    Next
End If
If e.Sender.SelectedValue = "空值"
    For i As Integer = 0 To e.Sender.Items.Count - 1
        If e.sender.Items(i) <> "全部" AndAlso e.sender.Items(i) <> "非空" Then
            e.Sender.SetItemChecked(i, e.Checked)
        Else
            e.Sender.SetItemChecked(i, False)
        End If
    Next
End If
systemready = True