Amoeba.Windows.LinkOptionsWindow._uploadUntrustSignatureListView_ContextMenuOpening C# (CSharp) Method

        private void _uploadUntrustSignatureListView_ContextMenuOpening(object sender, ContextMenuEventArgs e)
        {
            if (_uploadLinkListView.SelectedIndex == -1)
            {
                _uploadUntrustSignatureListViewDeleteMenuItem.IsEnabled = false;
                _uploadUntrustSignatureListViewCutMenuItem.IsEnabled = false;
                _uploadUntrustSignatureListViewCopyMenuItem.IsEnabled = false;
                _uploadUntrustSignatureListViewPasteMenuItem.IsEnabled = false;
            }
            else
            {
                var selectItems = _uploadUntrustSignatureListView.SelectedItems;

                _uploadUntrustSignatureListViewDeleteMenuItem.IsEnabled = (selectItems != null && selectItems.Count > 0);
                _uploadUntrustSignatureListViewCutMenuItem.IsEnabled = (selectItems != null && selectItems.Count > 0);
                _uploadUntrustSignatureListViewCopyMenuItem.IsEnabled = (selectItems != null && selectItems.Count > 0);

                {
                    bool flag = false;

                    if (Clipboard.ContainsText())
                    {
                        var line = Clipboard.GetText().Split('\r', '\n');
                        flag = Signature.Check(line[0]);
                    }

                    _uploadUntrustSignatureListViewPasteMenuItem.IsEnabled = flag;
                }
            }
        }