如何通過從文件中讀取來創建多級 MenuStrip？

Question

文本文件：

1;Laptop
2;Dell;1
3;Asus;1
4;Dell Vostro;2
5;RAM
6;RAM Kington;5
7;RAM Kingmax;5
8;RAM Kington 3GB;6
9;RAM Kingmax 2GB;7

這是我的代碼：

//Class item
class Item
{
    public string Id { get; set; }
    public string Name { get; set; }
    public string Parent { get; set; }
}

//Read file from file1.txt
static List<Item> GetItems()
{
    string[] lines = File.ReadAllLines("Item.txt");
    List<Item> list = new List<Item>();
    foreach (string line in lines)
    {
        string[] strItem = line.Split(';');
        Item item = new Item
        {
            Name = strItem[1],
            Id = strItem[0],
            Parent = strItem.Length > 2 ? strItem[2] : null
        };
        list.Add(item);
    }
    return list;
}

//Process input from file1.txt
private void Form1_Load(object sender, EventArgs e)
{
    List<Item> list = GetItems();

    foreach (Item item in list)
    {
        if (item.Parent is null)
        {
            ToolStripMenuItem menuItem = new ToolStripMenuItem(item.Name);
            msItem.Items.Add(menuItem);
            foreach (Item item2 in list)
            {
                if (item2.Parent == item.Id)
                {
                    ToolStripMenuItem menuItem1 = new ToolStripMenuItem(item2.Name);
                    menuItem.DropDownItems.Add(menuItem1);
                    foreach (Item item3 in list)
                    {
                        if (item3.Parent == item2.Id)
                        {
                            ToolStripMenuItem menuItem2 = new ToolStripMenuItem(item3.Name);
                            menuItem1.DropDownItems.Add(menuItem2);
                        }

                    }
                }
            }
        }
    }
}

但是如果我想創建一個 10 級深處的菜單，那么循環太多了，那就是 10 個嵌套循環。

那么如何優化代碼呢？

Answer 1

只需使用Dictionary<string, ToolStripMenuitem>這樣您就可以在創建菜單時查找它們：

private void Form1_Load(object sender, EventArgs e)
{
    Dictionary<string, ToolStripMenuItem> menuLookup = new Dictionary<string, ToolStripMenuItem>();
    List<Item> list = GetItems();

    foreach (Item item in list)
    {
        ToolStripMenuItem menuItem = new ToolStripMenuItem(item.Name);
        if (!menuLookup.ContainsKey(item.Id))
        {
            menuLookup.Add(item.Id, menuItem);
        }
        if (item.Parent is null)
        {                    
            msItem.Items.Add(menuItem);                    
        }
        else if (menuLookup.ContainsKey(item.Parent))
        {
            menuLookup[item.Parent].DropDownItems.Add(menuItem);
        }
    }
}