Question

我正在尝试以下代码从asp.net web api输出图像，但响应体长度始终为0.

public HttpResponseMessage GetImage()
{
    HttpResponseMessage response = new HttpResponseMessage();
    response.Content = new StreamContent(new FileStream(@"path to image"));
    response.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");

    return response;
}

任何提示？

WORKS：

    [HttpGet]
    public HttpResponseMessage Resize(string source, int width, int height)
    {
        HttpResponseMessage httpResponseMessage = new HttpResponseMessage();

        // Photo.Resize is a static method to resize the image
        Image image = Photo.Resize(Image.FromFile(@"d:\path\" + source), width, height);

        MemoryStream memoryStream = new MemoryStream();

        image.Save(memoryStream, ImageFormat.Jpeg);

        httpResponseMessage.Content = new ByteArrayContent(memoryStream.ToArray());

        httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
        httpResponseMessage.StatusCode = HttpStatusCode.OK;

        return httpResponseMessage;
    }

Answer 1

以下内容：

确保路径正确（duh）
确保您的路由正确无误。您的Controller是ImageController，或者您已经定义了一个自定义路由以支持其他控制器上的“GetImage”。（你应该得到404响应。）
确保您打开信息流：

var stream = new FileStream(path, FileMode.Open);

我尝试了类似的东西，它对我有用。

Answer 2

您还可以使用StreamContent类来更有效地使用流来代替ByteArrayContent。

使用web api输出图像HttpResponseMessage

2 个答案: