菜单导航功能实现，常规的管理系统应该常用，左侧显示菜单条目，点击菜单，右侧切换不同的业务用户控件。

常用菜单可以采用TreeView树形控件+特定样式实现 ，本文介绍的是使用Expander+ListView的组合形式实现的导航菜单，两种各有各的好处，本文不做优劣评价。

需要添加两个Nuget库：MaterialDesignThemes和MaterialDesignColors，本程序是使用该控件库实现的，非常强大

文件说明：

• App.xaml：只引入MD控件样式。
• MainWindow.展示导航菜单及控制菜单对应的用户控件切换。
• UserControlMenuItem为单个菜单用户控件，由 Expander+ListView的组合形式实现 。
• UserControlCustomers和UserControlProviders作为两个举例用的业务用户控件。
• ViewModel中定义的两个菜单相关的类，将菜单及业务用户控件关联。

App.xaml引入MD控件样式

主窗体

MainWindow.xaml，整体布局，看上图加上下面的界面代码，添加界面左上角logo图标、左侧导航菜单、右侧业务控件显示容器等。

MainWindow.xaml.cs，主窗体后台代码，没啥好说的，初始化菜单绑定数据、切换菜单显示用户控件。

using 侧边栏导航菜单_Dropdown_Menu_.ViewModel;
using MaterialDesignThemes.Wpf;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace 侧边栏导航菜单_Dropdown_Menu_
{/// 
/// MainWindow.xaml 的交互逻辑/// 
public partial class MainWindow : Window{public MainWindow(){InitializeComponent();var menuRegister = new List();menuRegister.Add(new SubItem("客户", new UserControlCustomers()));menuRegister.Add(new SubItem("供应商", new UserControlProviders()));menuRegister.Add(new SubItem("员工"));menuRegister.Add(new SubItem("产品"));var item6 = new ItemMenu("登记", menuRegister, PackIconKind.Register);var menuSchedule = new List();menuSchedule.Add(new SubItem("服务"));menuSchedule.Add(new SubItem("会议"));var item1 = new ItemMenu("预约", menuSchedule, PackIconKind.Schedule);var menuReports = new List();menuReports.Add(new SubItem("客户"));menuReports.Add(new SubItem("供应商"));menuReports.Add(new SubItem("产品"));menuReports.Add(new SubItem("库存"));menuReports.Add(new SubItem("销售额"));var item2 = new ItemMenu("报告", menuReports, PackIconKind.FileReport);var menuExpenses = new List();menuExpenses.Add(new SubItem("固定资产"));menuExpenses.Add(new SubItem("流动资金"));var item3 = new ItemMenu("费用", menuExpenses, PackIconKind.ShoppingBasket);var menuFinancial = new List();menuFinancial.Add(new SubItem("现金流"));var item4 = new ItemMenu("财务", menuFinancial, PackIconKind.ScaleBalance);Menu.Children.Add(new UserControlMenuItem(item6, this));Menu.Children.Add(new UserControlMenuItem(item1, this));Menu.Children.Add(new UserControlMenuItem(item2, this));Menu.Children.Add(new UserControlMenuItem(item3, this));Menu.Children.Add(new UserControlMenuItem(item4, this));}internal void SwitchScreen(object sender){var screen = ((UserControl)sender);if (screen != null){StackPanelMain.Children.Clear();StackPanelMain.Children.Add(screen);}}}
}

导航子菜单用户控件

UserControlMenuItem.xaml

UserControlMenuItem.xaml.cs，后台代码实现

using 侧边栏导航菜单_Dropdown_Menu_.ViewModel;
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace 侧边栏导航菜单_Dropdown_Menu_
{/// 
/// UserControlMenuItem.xaml 的交互逻辑/// 
public partial class UserControlMenuItem : UserControl{MainWindow _context;public UserControlMenuItem(ItemMenu itemMenu, MainWindow context){InitializeComponent();_context = context;ExpanderMenu.Visibility = itemMenu.SubItems == null ? Visibility.Collapsed : Visibility.Visible;ListViewItemMenu.Visibility = itemMenu.SubItems == null ? Visibility.Visible : Visibility.Collapsed;this.DataContext = itemMenu;}private void ListViewMenu_SelectionChanged(object sender, SelectionChangedEventArgs e){_context.SwitchScreen(((SubItem)((ListView)sender).SelectedItem).Screen);}}
}

菜单ViewModel类

ItemMenu.cs

using MaterialDesignThemes.Wpf;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;namespace 侧边栏导航菜单_Dropdown_Menu_.ViewModel
{public class ItemMenu{public ItemMenu(string header, List subItems, PackIconKind icon){Header = header;SubItems = subItems;Icon = icon;}public string Header { get; private set; }public PackIconKind Icon { get; private set; }public List SubItems { get; private set; }public UserControl Screen { get; private set; }}
}

SubItem.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;namespace 侧边栏导航菜单_Dropdown_Menu_.ViewModel
{public class SubItem{public SubItem(string name, UserControl screen = null){Name = name;Screen = screen;}public string Name { get; private set; }public UserControl Screen { get; private set; }}
}

两个举例用的用户控件

UserControlCustomers.xaml

UserControlProviders.xaml

文章中代码几乎已经全部贴出，就是这么多。

效果如下：