我有两个选择:

1)实现你自己的IViewEngine，设置控制器的ViewEngine属性，你正在使用你的ImageViewEngine在你想要的“image”方法。

2)使用视图:-)。只需改变内容类型等。

稍微解释一下迪兰的回应:

有三个类实现了FileResult类:

System.Web.Mvc.FileResult
      System.Web.Mvc.FileContentResult
      System.Web.Mvc.FilePathResult
      System.Web.Mvc.FileStreamResult

它们都是不言自明的:

For file path downloads where the file exists on disk, use FilePathResult - this is the easiest way and avoids you having to use Streams. For byte[] arrays (akin to Response.BinaryWrite), use FileContentResult. For byte[] arrays where you want the file to download (content-disposition: attachment), use FileStreamResult in a similar way to below, but with a MemoryStream and using GetBuffer(). For Streams use FileStreamResult. It's called a FileStreamResult but it takes a Stream so I'd guess it works with a MemoryStream.

下面是一个使用内容处理技术的例子(未测试):

    [AcceptVerbs(HttpVerbs.Post)]
    public ActionResult GetFile()
    {
        // No need to dispose the stream, MVC does it for you
        string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "App_Data", "myimage.png");
        FileStream stream = new FileStream(path, FileMode.Open);
        FileStreamResult result = new FileStreamResult(stream, "image/png");
        result.FileDownloadName = "image.png";
        return result;
    }

更新:有比我原来的答案更好的选择。这在MVC之外工作得很好，但最好坚持使用返回图像内容的内置方法。见赞成投票的答案。

你当然可以。试试下面这些步骤:

将映像从磁盘加载到字节数组中 缓存图像，如果您希望对图像有更多的请求，并且不需要磁盘I/O(我的示例在下面没有缓存它) 通过响应改变mime类型。ContentType 响应。写出图像字节数组

下面是一些示例代码:

string pathToFile = @"C:\Documents and Settings\some_path.jpg";
byte[] imageData = File.ReadAllBytes(pathToFile);
Response.ContentType = "image/jpg";
Response.BinaryWrite(imageData);

希望有帮助!

读取图像，将其转换为byte[]，然后返回具有内容类型的File()。

public ActionResult ImageResult(Image image, ImageFormat format, string contentType) {
  using (var stream = new MemoryStream())
    {
      image.Save(stream, format);
      return File(stream.ToArray(), contentType);
    }
  }
}

以下是用法:

using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using Microsoft.AspNetCore.Mvc;

您可以直接写入响应，但这样它就不可测试了。最好返回一个延迟执行的ActionResult。这是我的可重用StreamResult:

public class StreamResult : ViewResult
{
    public Stream Stream { get; set; }
    public string ContentType { get; set; }
    public string ETag { get; set; }

    public override void ExecuteResult(ControllerContext context)
    {
        context.HttpContext.Response.ContentType = ContentType;
        if (ETag != null) context.HttpContext.Response.AddHeader("ETag", ETag);
        const int size = 4096;
        byte[] bytes = new byte[size];
        int numBytes;
        while ((numBytes = Stream.Read(bytes, 0, size)) > 0)
            context.HttpContext.Response.OutputStream.Write(bytes, 0, numBytes);
    }
}

这对我很管用。 因为我将图像存储在SQL Server数据库上。

    [HttpGet("/image/{uuid}")]
    public IActionResult GetImageFile(string uuid) {
        ActionResult actionResult = new NotFoundResult();
        var fileImage = _db.ImageFiles.Find(uuid);
        if (fileImage != null) {
            actionResult = new FileContentResult(fileImage.Data,
                fileImage.ContentType);
        }
        return actionResult;
    }

在上面的代码片段中，_db.ImageFiles.Find(uuid)正在db (EF上下文)中搜索图像文件记录。它返回一个FileImage对象，它只是一个我为模型制作的自定义类，然后将其用作FileContentResult。

public class FileImage {
   public string Uuid { get; set; }
   public byte[] Data { get; set; }
   public string ContentType { get; set; }
}