CardMaker.Forms.MDIProject.addReferenceToolStripMenuItem_Click C# (CSharp) Метод

        private void addReferenceToolStripMenuItem_Click(object sender, EventArgs e)
        {
            var sFile = FormUtils.FileOpenHandler("CSV files (*.csv)|*.csv|All files (*.*)|*.*", null, true);
            if (null != sFile)
            {
                var zLayout = (ProjectLayout)treeView.SelectedNode.Tag;
                var bNewDefault = 0 == treeView.SelectedNode.Nodes.Count;
                var tnReference = AddReferenceNode(treeView.SelectedNode, sFile, bNewDefault, zLayout);
                if (null == tnReference)
                {
                    MessageBox.Show(this, "The specified reference is already associated with this layout.", "Reference Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    return;
                }
                if (bNewDefault)
                {
                    tnReference.Parent.Expand();
                    LayoutManager.Instance.RefreshActiveLayout();

                }
                ProjectManager.Instance.FireProjectUpdated(true);
            }
        }