abp web.mvc項目中的菜單加載機制

abp中的菜單加載機制

在abp中菜單的定義與我們傳統寫的框架不一樣，它是在編寫代碼的時候配置，而我們一般寫的通用權限管理系統中，是後期在後臺界面中添加的。這一點有很大不同。abp關於菜單的定義及管理挺複雜的。

與菜單相關的結構類、接口及擴展方法類

• MenuDefinition：定義應用程序的菜單的結構
• MenuItemDefinition：定義應用程序的菜單項的結構
• IHasMenuItemDefinitions: 定義子菜單的接口
• HasMenuItemDefinitionsExtensions：查詢子菜單項的擴展方法類
• MenuItemDefinitionExtensions：操作菜單項的擴展方法類
  

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• UserMenu:單個用戶的菜單結構
• UserMenuItem：單個用戶的菜單中的菜單項

與菜單相關的操作類

這裏分爲兩類，一類是針對應用系統的菜單：

• NavigationProvider:提供設置應用系統導航菜單及菜單項的方法SetNavigation
• INavigationProviderContext：Provider模式的上下文接口
• NavigationProviderContext：Provider模式的上下文類，設置NavigationManager
• INavigationManager：導航菜單管理應用服務接口
• NavigationManager：導航菜單管理應用服務類，包括構造默認主菜單，初始化菜單的所有菜單項方法。
  
  另一類是針對用戶菜單的操作：
• IUserNavigationManager: 用戶菜單管理應用服務接口
• UserNavigationManager：用戶菜單管理應用服務類，提供了獲取指定用戶的菜單， 根據用戶權限填充菜單項方法。

上面的所有類及接口都是在Abp這個項目中定義的。

Web.MVC中的菜單應用

菜單的定義

菜單定義在ContosoAbp.Web.Startup命名空間下的ContosoAbpNavigationProvider類中，這裏ContosoAbp爲自定義的項目名。ContosoAbpNavigationProvide繼承自NavigationProvider抽象類，是實際菜單的定義者。這裏利用了Provider模式，微軟經常用這種模式。

using Abp.Application.Navigation;
using Abp.Authorization;
using Abp.Localization;
using ContosoAbp.Authorization;

namespace ContosoAbp.Web.Startup
{
    /// <summary>
    /// This class defines menus for the application.
    /// 定義應用程序的菜單
    /// </summary>
    public class ContosoAbpNavigationProvider : NavigationProvider
    {
        public override void SetNavigation(INavigationProviderContext context)
        {
            context.Manager.MainMenu
                .AddItem(
                    new MenuItemDefinition( //首頁
                        PageNames.Home,
                        L("HomePage"),
                        url: "",
                        icon: "fas fa-home",
                        requiresAuthentication: true,
                        order:0
                    )
                ).AddItem(
                    new MenuItemDefinition( //空頁面
                        PageNames.Empty,
                        L("EmptyPage"),
                        url: "Home/Empty",
                        icon: "fas fa-home",
                        requiresAuthentication: false,
                        order: 1
                    )
                ).AddItem(
                    new MenuItemDefinition( //附件
                        PageNames.Attachment,
                        L("Attachment"),
                        url: "Attachment",
                        icon: "fas fa-home",
                        requiresAuthentication: false,
                        order: 2
                    )
                ).AddItem(
                    new MenuItemDefinition( //租戶
                        PageNames.Tenants,
                        L("Tenants"),
                        url: "Tenants",
                        icon: "fas fa-building",
                        permissionDependency: new SimplePermissionDependency(PermissionNames.Pages_Tenants),
                        order: 3
                    )
                ).AddItem(
                    new MenuItemDefinition( // 用戶
                        PageNames.Users,
                        L("Users"),
                        url: "Users",
                        icon: "fas fa-users",
                        permissionDependency: new SimplePermissionDependency(PermissionNames.Pages_Users),
                        order: 4
                    )
                ).AddItem(
                    new MenuItemDefinition( //角色
                        PageNames.Roles,
                        L("Roles"),
                        url: "Roles",
                        icon: "fas fa-theater-masks",
                        permissionDependency: new SimplePermissionDependency(PermissionNames.Pages_Roles),
                        order: 5
                            )
                )
                .AddItem(
                    new MenuItemDefinition( //關於
                        PageNames.About,
                        L("About"),
                        url: "About",
                        icon: "fas fa-info-circle",
                        order: 6
                    )
                ).AddItem( // Menu items below is just for demonstration!
                    new MenuItemDefinition( //多級菜單
                        "MultiLevelMenu",
                        L("MultiLevelMenu"),
                        icon: "fas fa-circle",
                        order: 7
                    ).AddItem(
                        new MenuItemDefinition(
                            "AspNetBoilerplate",
                            new FixedLocalizableString("ASP.NET Boilerplate"),
                            icon: "far fa-circle"
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetBoilerplateHome",
                                new FixedLocalizableString("Home"),
                                url: "https://aspnetboilerplate.com?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetBoilerplateTemplates",
                                new FixedLocalizableString("Templates"),
                                url: "https://aspnetboilerplate.com/Templates?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetBoilerplateSamples",
                                new FixedLocalizableString("Samples"),
                                url: "https://aspnetboilerplate.com/Samples?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetBoilerplateDocuments",
                                new FixedLocalizableString("Documents"),
                                url: "https://aspnetboilerplate.com/Pages/Documents?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        )
                    ).AddItem(
                        new MenuItemDefinition(
                            "AspNetZero",
                            new FixedLocalizableString("ASP.NET Zero"),
                            icon: "far fa-circle"
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetZeroHome",
                                new FixedLocalizableString("Home"),
                                url: "https://aspnetzero.com?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetZeroFeatures",
                                new FixedLocalizableString("Features"),
                                url: "https://aspnetzero.com/Features?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetZeroPricing",
                                new FixedLocalizableString("Pricing"),
                                url: "https://aspnetzero.com/Pricing?ref=abptmpl#pricing",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetZeroFaq",
                                new FixedLocalizableString("Faq"),
                                url: "https://aspnetzero.com/Faq?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        ).AddItem(
                            new MenuItemDefinition(
                                "AspNetZeroDocuments",
                                new FixedLocalizableString("Documents"),
                                url: "https://aspnetzero.com/Documents?ref=abptmpl",
                                icon: "far fa-dot-circle"
                            )
                        )
                    )
                );
        }

        private static ILocalizableString L(string name)
        {
            return new LocalizableString(name, ContosoAbpConsts.LocalizationSourceName);
        }
    }
}

菜單的加載

菜單的加載是利用的視圖組件，定義了一個SideBarMenuViewComponent的視圖組件，在這個SideBarMenuViewComponent類中，利用IUserNavigationManager獲取用戶的菜單，返回SideBarMenuViewModel給前端，前端遍歷輸出菜單及子項。

後端視圖組件的定義

using System.Threading.Tasks;
using Abp.Application.Navigation;
using Abp.Runtime.Session;
using Microsoft.AspNetCore.Mvc;

namespace ContosoAbp.Web.Views.Shared.Components.SideBarMenu
{
    /// <summary>
    /// 側邊欄視圖組件
    /// </summary>
    public class SideBarMenuViewComponent : ContosoAbpViewComponent
    {
        /// <summary>
        /// 側邊欄用戶導航管理
        /// </summary>
        private readonly IUserNavigationManager _userNavigationManager;

        /// <summary>
        /// Session服務
        /// </summary>
        private readonly IAbpSession _abpSession;

        /// <summary>
        /// 構造函數
        /// </summary>
        /// <param name="userNavigationManager"></param>
        /// <param name="abpSession"></param>
        public SideBarMenuViewComponent(
            IUserNavigationManager userNavigationManager,
            IAbpSession abpSession)
        {
            _userNavigationManager = userNavigationManager;
            _abpSession = abpSession;
        }

        public async Task<IViewComponentResult> InvokeAsync()
        {
            var model = new SideBarMenuViewModel
            {
                MainMenu = await _userNavigationManager.GetMenuAsync("MainMenu", _abpSession.ToUserIdentifier())
            };

            return View(model);
        }
    }
}

前端遍歷輸出菜單

@using ContosoAbp.Web.Views.Shared.Components.SideBarMenu
@model SideBarMenuViewModel
@{ 
    var orderedMenuItems = Model.MainMenu.Items.Where(x => x.IsVisible).OrderByCustom().ToList();
}

<nav class="mt-2">
    <ul class="nav nav-pills nav-sidebar flex-column nav-flat" data-widget="treeview" role="menu" data-accordion="false">
        @{
            foreach (var item in orderedMenuItems)
            {
                @await Html.PartialAsync("Components/SideBarMenu/_MenuItem", item)
            }
        }
    </ul>
</nav>