(1)要向窗体添加一个TreeView控件

(2)再添加一个ContextMenuStrip控件；

(3)就要给TreeView添加一个MouseDown事件，代码如下：

private void treeView1_MouseDown(object sender, MouseEventArgs e)
        ...{
            if (e.Button == MouseButtons.Right)//判断你点的是不是右键
            ...{
                Point ClickPoint = new Point(e.X, e.Y);
                TreeNode CurrentNode = treeView1.GetNodeAt(ClickPoint);
                if (CurrentNode != null)//判断你点的是不是一个节点
                ...{
                    switch (CurrentNode.Name)//根据不同节点显示不同的右键菜单，当然你可以让它显示一样的菜单
                    ...{
                        case "errorUrl":
                            CurrentNode.ContextMenuStrip = contextMenuStripErrorUrl;
                            break;
                    }
                    treeView1.SelectedNode = CurrentNode;//选中这个节点
                }
            }
        }