[译]ASP.NET Core 2.0 本地文件操作
2021-05-15 13:00
标签:一个 singleton log files 程序启动 output csharp steam std 如何在ASP.NET Core 2.0中受限地访问本地目录和文件信息? 新建一个空项目,修改Startup类,添加访问本地文件所需的服务: 创建一个中间件,读取根目录下的所有文件,输出文件名: 运行,此时页面效果: 当然,我们也可以通过IFileProvider接口读取单个文件信息: 运行,此时页面效果: ASP.NET Core 2.0提供了继承自接口IFileProvider的PhysicalFileProvider类型,用于受限地访问本地文件系统,它是对System.IO.File的一个封装。 我们可以在Startup的Configure()方法内将IFileProvider配置为一个服务,然后通过构造函数注入添加到中间件或者控制器中。这样可以在一个地方控制文件的访问路径(也就是应用程序启动的时候)。 IFileProvider有两个重要的方法: 1. GetDirectoryContents:返回IDirectoryContents接口。可用于遍历某个目录中的全部文件或目录。 2. GetFileInfo:返回IFileInfo接口。通过其CreateReadSteam方法可以读取文件内容。 ====start by sanshi========================= 下面通过递归来遍历根目录下全部文件和目录,修改中间件代码: 运行,此时页面效果: ====end by sanshi========================= 原文:https://tahirnaushad.com/2017/08/18/asp-net-core-file-providers/ [译]ASP.NET Core 2.0 本地文件操作 标签:一个 singleton log files 程序启动 output csharp steam std 原文地址:http://www.cnblogs.com/sanshi/p/7735941.html问题
答案
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton
public class HelloFileProviderMiddleware
{
private readonly RequestDelegate _next;
private readonly IFileProvider _fileProvider;
public HelloFileProviderMiddleware(RequestDelegate next, IFileProvider fileProvider)
{
_next = next;
_fileProvider = fileProvider;
}
public async Task Invoke(HttpContext context)
{
var output = new StringBuilder("");
IDirectoryContents dir = _fileProvider.GetDirectoryContents("");
foreach (IFileInfo item in dir)
{
output.AppendLine(item.Name);
}
await context.Response.WriteAsync(output.ToString());
}
}
public static class UseHelloFileProviderExtensions
{
public static IApplicationBuilder UseHelloFileProvider(this IApplicationBuilder app)
{
return app.UseMiddleware
public class HelloFileProviderMiddleware
{
private readonly RequestDelegate _next;
private readonly IFileProvider _fileProvider;
public HelloFileProviderMiddleware(RequestDelegate next, IFileProvider fileProvider)
{
_next = next;
_fileProvider = fileProvider;
}
public async Task Invoke(HttpContext context)
{
IFileInfo file = _fileProvider.GetFileInfo("Startup.cs");
using (var stream = file.CreateReadStream())
{
using (var reader = new StreamReader(stream))
{
var output = await reader.ReadToEndAsync();
await context.Response.WriteAsync(output.ToString());
}
}
}
}
讨论
public class HelloFileProviderMiddleware
{
private readonly RequestDelegate _next;
private readonly IFileProvider _fileProvider;
public HelloFileProviderMiddleware(RequestDelegate next, IFileProvider fileProvider)
{
_next = next;
_fileProvider = fileProvider;
}
public async Task Invoke(HttpContext context)
{
var output = new StringBuilder("");
ResolveDirectory(output, "", "");
await context.Response.WriteAsync(output.ToString());
}
private void ResolveDirectory(StringBuilder output, string path, string prefix)
{
IDirectoryContents dir = _fileProvider.GetDirectoryContents(path);
foreach (IFileInfo item in dir)
{
if (item.IsDirectory)
{
output.AppendLine(prefix + "[" + item.Name + "]");
ResolveDirectory(output,
item.PhysicalPath.Substring(Directory.GetCurrentDirectory().Length),
prefix + " ");
} else
{
output.AppendLine(prefix + item.Name);
}
}
}
}
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