aspnetcore/src/Microsoft.AspNetCore.Mvc.Core/FileResult.cs

90 lines
3.4 KiB
C#

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc.Internal;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Net.Http.Headers;
namespace Microsoft.AspNetCore.Mvc
{
/// <summary>
/// Represents an <see cref="ActionResult"/> that when executed will
/// write a file as the response.
/// </summary>
public abstract class FileResult : ActionResult
{
private string _fileDownloadName;
/// <summary>
/// Creates a new <see cref="FileResult"/> instance with
/// the provided <paramref name="contentType"/>.
/// </summary>
/// <param name="contentType">The Content-Type header of the response.</param>
protected FileResult(string contentType)
{
if (contentType == null)
{
throw new ArgumentNullException(nameof(contentType));
}
ContentType = contentType;
}
/// <summary>
/// Gets the Content-Type header for the response.
/// </summary>
public string ContentType { get; }
/// <summary>
/// Gets the file name that will be used in the Content-Disposition header of the response.
/// </summary>
public string FileDownloadName
{
get { return _fileDownloadName ?? string.Empty; }
set { _fileDownloadName = value; }
}
/// <inheritdoc />
public override Task ExecuteResultAsync(ActionContext context)
{
if (context == null)
{
throw new ArgumentNullException(nameof(context));
}
var loggerFactory = context.HttpContext.RequestServices.GetRequiredService<ILoggerFactory>();
var logger = loggerFactory.CreateLogger<FileResult>();
var response = context.HttpContext.Response;
response.ContentType = ContentType.ToString();
if (!string.IsNullOrEmpty(FileDownloadName))
{
// From RFC 2183, Sec. 2.3:
// The sender may want to suggest a filename to be used if the entity is
// detached and stored in a separate file. If the receiving MUA writes
// the entity to a file, the suggested filename should be used as a
// basis for the actual filename, where possible.
var contentDisposition = new ContentDispositionHeaderValue("attachment");
contentDisposition.SetHttpFileName(FileDownloadName);
context.HttpContext.Response.Headers[HeaderNames.ContentDisposition] = contentDisposition.ToString();
}
logger.FileResultExecuting(FileDownloadName);
return WriteFileAsync(response);
}
/// <summary>
/// Writes the file to the specified <paramref name="response"/>.
/// </summary>
/// <param name="response">The <see cref="HttpResponse"/>.</param>
/// <returns>
/// A <see cref="Task"/> that will complete when the file has been written to the response.
/// </returns>
protected abstract Task WriteFileAsync(HttpResponse response);
}
}