private void InitTreeView()
{
this.docMenu = new ContextMenuStrip();
var deleteLabel = new ToolStripMenuItem { Text = "Delete" };
var addLabel = new ToolStripMenuItem { Text = "Add" };
deleteLabel.Click += DeleteLabelOnClick;
addLabel.Click += AddLabelOnClick;
this.docMenu.Items.AddRange(new ToolStripMenuItem[] { addLabel, deleteLabel });
this.treeView.ContextMenuStrip = this.docMenu;
treeView.LabelEdit = true;
}