Abp源码分析之虚拟文件系统Volo.Abp.VirtualFileSystem

前言

Volo.Abp.VirtualFileSystem 是ABP（ASP.NET Boilerplate）框架中的一个重要组件，它提供了一种抽象文件系统的方式，使得应用程序可以轻松地访问和管理文件资源，无论这些资源是来自于物理文件系统、嵌入资源，还是远程存储。

通过Volo.Abp.VirtualFileSystem，开发者可以使用统一的接口来处理文件和目录，而不用关心这些文件和目录的实际存储位置。这使得应用程序更加灵活，可以轻松地切换不同的文件存储方式，而不用修改大量的代码。

新建mvc项目

引用以下nuget包

新建BookAppWebModule.cs

using Volo.Abp.Localization.ExceptionHandling;
using Volo.Abp.Localization;
using Volo.Abp.Modularity;
using Volo.Abp.VirtualFileSystem;
using Volo.Abp.Autofac;
using Volo.Abp.AspNetCore.Mvc;
using Volo.Abp;
using Volo.Abp.AspNetCore.Mvc.Localization;
using Microsoft.AspNetCore.Mvc.Razor;
using Microsoft.Extensions.Hosting.Internal;
using BookApp.Localization;
using BookCategory;

namespace BookApp
{
    [DependsOn(
        typeof(AbpAutofacModule),
        typeof(AbpLocalizationModule),
        typeof(AbpVirtualFileSystemModule),
        typeof(AbpAspNetCoreMvcModule),
        typeof(BookCategoryModule)
    )]
    public class BookAppWebModule: AbpModule
    {
        public override void PreConfigureServices(ServiceConfigurationContext context)
        {
            var hostingEnvironment = context.Services.GetHostingEnvironment();
            var configuration = context.Services.GetConfiguration();

            context.Services.PreConfigure<AbpMvcDataAnnotationsLocalizationOptions>(options =>
            {
                options.AddAssemblyResource(
                    typeof(BookStoreResource)
                );
            });
        }
        public override void ConfigureServices(ServiceConfigurationContext context)
        {
            var hostingEnvironment = context.Services.GetHostingEnvironment();

            ConfigureVirtualFileSystem(hostingEnvironment);

            Configure<AbpLocalizationOptions>(options =>
            {
                options.Languages.Add(new LanguageInfo("ar", "ar", "العربية"));
                options.Languages.Add(new LanguageInfo("cs", "cs", "Čeština"));
                options.Languages.Add(new LanguageInfo("en", "en", "English"));
                options.Languages.Add(new LanguageInfo("en-GB", "en-GB", "English (UK)"));
                options.Languages.Add(new LanguageInfo("hu", "hu", "Magyar"));
                options.Languages.Add(new LanguageInfo("fi", "fi", "Finnish"));
                options.Languages.Add(new LanguageInfo("fr", "fr", "Français"));
                options.Languages.Add(new LanguageInfo("hi", "hi", "Hindi"));
                options.Languages.Add(new LanguageInfo("it", "it", "Italiano"));
                options.Languages.Add(new LanguageInfo("pt-BR", "pt-BR", "Português"));
                options.Languages.Add(new LanguageInfo("ru", "ru", "Русский"));
                options.Languages.Add(new LanguageInfo("sk", "sk", "Slovak"));
                options.Languages.Add(new LanguageInfo("tr", "tr", "Türkçe"));
                options.Languages.Add(new LanguageInfo("zh-Hans", "zh-Hans", "简体中文"));
                options.Languages.Add(new LanguageInfo("zh-Hant", "zh-Hant", "繁體中文"));
                options.Languages.Add(new LanguageInfo("de-DE", "de-DE", "Deutsch"));
                options.Languages.Add(new LanguageInfo("es", "es", "Español"));

                options.Resources
                    .Add<BookStoreResource>("en")
                    .AddVirtualJson("/Localization/BookStore");

                options.DefaultResourceType = typeof(BookStoreResource);
            });
        }

        public override void OnApplicationInitialization(ApplicationInitializationContext context)
        {
            var app = context.GetApplicationBuilder();
            var env = context.GetEnvironment();

            app.UseAbpRequestLocalization();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();

            app.UseRouting();
        }

        private void ConfigureVirtualFileSystem(IWebHostEnvironment hostingEnvironment)
        {
            Configure<AbpVirtualFileSystemOptions>(options =>
            {
                options.FileSets.AddEmbedded<BookAppWebModule>();

                if (hostingEnvironment.IsDevelopment())
                {
                    options.FileSets.ReplaceEmbeddedByPhysical<BookAppWebModule>(hostingEnvironment.ContentRootPath);
                    options.FileSets.ReplaceEmbeddedByPhysical<BookCategoryModule>(Path.Combine(hostingEnvironment.ContentRootPath, string.Format("..{0}BookCategory", Path.DirectorySeparatorChar)));
                }
            });
        }
    }
}

修改Program.cs

using BookApp;
using Microsoft.Extensions.DependencyInjection;

var builder = WebApplication.CreateBuilder(args);

builder.Host
    .AddAppSettingsSecretsJson()
    .UseAutofac();

await builder.AddApplicationAsync<BookAppWebModule>();

var app = builder.Build();

await app.InitializeApplicationAsync();

app.MapControllerRoute(
    name: "default",
    pattern: "{controller=Home}/{action=Index}/{id?}");

await app.RunAsync();

新建资源文件

新建BookCategory类库项目

新建BookCategoryModule.cs

using Volo.Abp.Localization;
using Volo.Abp.Modularity;
using Volo.Abp.VirtualFileSystem;
using Volo.Abp;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.DependencyInjection;
using Volo.Abp.AspNetCore.Mvc;
using BookApp.Localization;

namespace BookCategory
{
    [DependsOn(
        typeof(AbpVirtualFileSystemModule),
        typeof(AbpAspNetCoreMvcModule)
    )]
    public class BookCategoryModule: AbpModule
    {
        public override void ConfigureServices(ServiceConfigurationContext context)
        {
            var hostingEnvironment = context.Services.GetHostingEnvironment();
            var configuration = context.Services.GetConfiguration();

            Configure<AbpVirtualFileSystemOptions>(options =>
            {
                options.FileSets.AddEmbedded<BookCategoryModule>();//添加程序集到虚拟文件系统

                if (hostingEnvironment.IsDevelopment())
                {

                }
            });

            Configure<AbpLocalizationOptions>(options =>
            {
                options.Resources
                    .Add<BookCategoryResource>("en")
                    .AddVirtualJson("/Localization/BookCategory"); //这里必需添加，不然本地化时找不到相应的json文件
            });
        }

        public override void OnApplicationInitialization(ApplicationInitializationContext context)
        {

        }
    }
}

新建BookCategoryResource.cs

using Volo.Abp.Localization;

namespace BookApp.Localization;

[LocalizationResourceName("BookCategory")]
public class BookCategoryResource
{

}

新建资源文件

修改mvc项目的HomeController.cs中的Privacy方法

        public IActionResult Privacy()
        {
            var resourcePath = "/Localization/BookCategory/en.json";
            var fileInfo = _fileProvider.GetFileInfo(resourcePath);

            if (fileInfo.Exists)
            {
                using (var stream = fileInfo.CreateReadStream())
                using (var reader = new StreamReader(stream))
                {
                    var content = reader.ReadToEnd();
                    return Content(content);
                }
            }

            return Content("Resource not found");
        }

此时我们就可以访问BookCategory类库中的资源文件

修改mvc项目中的视图Index.cshtml

@using Microsoft.Extensions.Localization
@using Microsoft.AspNetCore.Mvc.Localization
@using BookApp.Controllers
@using BookApp.Localization

@inject IHtmlLocalizer<BookStoreResource> HtmlLocalizer
@inject IStringLocalizer<BookCategoryResource> StringLocalizer

@{
    ViewData["Title"] = "Home Page";
}

<div>string: @StringLocalizer["AppName"]</div>

<div>html: @HtmlLocalizer["AppName"]</div>

IStringLocalizer StringLocalizer 这里就可以读取BookCategory类库中的资源文件

作者

吴晓阳（手机：13736969112微信同号）