我正在开发一个使用Xamarin的Android应用程序，将文件上传到服务器。我的服务器是基于asp.net的，由azure托管。当代码尝试将文件写入服务器目录时，Xamarin会抛出此错误。我用来将文件发布到服务器的代码如下：
public async Task<HttpResponseMessage> UploadFile(byte[] file)
{
videoThumbName = Guid.NewGuid().ToString();
var progress = new System.Net.Http.Handlers.ProgressMessageHandler();
progress.HttpSendProgress += progress_HttpSendProgress;
using (var client = HttpClientFactory.Create(progress))
{
client.BaseAddress = new Uri(GlobalVariables.host);
// Set the Accept header for BSON.
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/bson"));
var request = new uploadFileModel { data = file, dateCreated = DateTime.Now, fileName = fileName, username = loggedUser, VideoThumbName = videoThumbName};
// POST using the BSON formatter.
MediaTypeFormatter bsonFormatter = new BsonMediaTypeFormatter();
var m = client.MaxResponseContentBufferSize;
var result = await client.PostAsync("api/media/upload", request, bsonFormatter);
return result.EnsureSuccessStatusCode();
}
}
我尝试过使用try catch块，奇怪的是即使在将文件写入路径并且我得到500内部服务器错误后也会捕获异常。到目前为止，我尝试上传的每个文件都保存到路径中，但我无法弄清楚为什么会发生错误。
我的服务器端代码如下所示：
[HttpPost]
[Route("upload")]
public async Task<HttpResponseMessage> Upload(uploadFileModel model)
{
var result = new HttpResponseMessage(HttpStatusCode.OK);
if (ModelState.IsValid)
{
string thumbname = "";
string resizedthumbname = Guid.NewGuid() + "_yt.jpg";
string FfmpegPath = Encoding_Settings.FFMPEGPATH;
string tempFilePath = Path.Combine(HttpContext.Current.Server.MapPath("~/tempuploads"), model.fileName);
string pathToFiles = HttpContext.Current.Server.MapPath("~/tempuploads");
string pathToThumbs = HttpContext.Current.Server.MapPath("~/contents/member/" + model.username + "/thumbs");
string finalPath = HttpContext.Current.Server.MapPath("~/contents/member/" + model.username + "/flv");
string resizedthumb = Path.Combine(pathToThumbs, resizedthumbname);
var outputPathVid = new MediaFile { Filename = Path.Combine(finalPath, model.fileName) };
var inputPathVid = new MediaFile { Filename = Path.Combine(pathToFiles, model.fileName) };
int maxWidth = 380;
int maxHeight = 360;
var namewithoutext = Path.GetFileNameWithoutExtension(Path.Combine(pathToFiles, model.fileName));
thumbname = model.VideoThumbName;
string oldthumbpath = Path.Combine(pathToThumbs, thumbname);
var fileName = model.fileName;
try
{
File.WriteAllBytes(tempFilePath, model.data);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
if (model.fileName.Contains("audio"))
{
File.WriteAllBytes(Path.Combine(finalPath, model.fileName), model.data);
string audio_thumb = "mic_thumb.jpg";
string destination = Path.Combine(pathToThumbs, audio_thumb);
string source = Path.Combine(pathToFiles, audio_thumb);
if (!System.IO.File.Exists(destination))
{
System.IO.File.Copy(source, destination, true);
}
Video_Struct vd = new Video_Struct();
vd.CategoryID = 0; // store categoryname or term instead of category id
vd.Categories = "";
vd.UserName = model.username;
vd.Title = "";
vd.Description = "";
vd.Tags = "";
vd.OriginalVideoFileName = model.fileName;
vd.VideoFileName = model.fileName;
vd.ThumbFileName = "mic_thumb.jpg";
vd.isPrivate = 0;
vd.AuthKey = "";
vd.isEnabled = 1;
vd.Response_VideoID = 0; // video responses
vd.isResponse = 0;
vd.isPublished = 1;
vd.isReviewed = 1;
vd.Thumb_Url = "none";
//vd.FLV_Url = flv_url;
vd.Embed_Script = "";
vd.isExternal = 0; // website own video, 1: embed video
vd.Type = 0;
vd.YoutubeID = "";
vd.isTagsreViewed = 1;
vd.Mode = 0; // filter videos based on website sections
long videoid = VideoBLL.Process_Info(vd, false);
}
这个例外并没有让我理解这个问题。奇怪的是，当我向本地服务器发送请求时，我没有收到任何错误。知道这里可能有什么问题吗？
修改
当我在代码的这一行using (var engine = new Engine())收到内部服务器错误时，不再出现异常这是我试图用来编码媒体文件的库。如果一切都在本地服务器上工作，那么为什么它不在实时服务器上：/
using (var engine = new Engine())
{
engine.GetMetadata(inputPathVid);
// Saves the frame located on the 15th second of the video.
var outputPathThumb = new MediaFile { Filename = Path.Combine(pathToThumbs, thumbname+".jpg") };
var options = new ConversionOptions { Seek = TimeSpan.FromSeconds(0), CustomHeight = 360, CustomWidth = 380 };
engine.GetThumbnail(inputPathVid, outputPathThumb, options);
}
Image image = Image.FromFile(Path.Combine(pathToThumbs, thumbname+".jpg"));
//var ratioX = (double)maxWidth / image.Width;
//var ratioY = (double)maxHeight / image.Height;
//var ratio = Math.Min(ratioX, ratioY);
var newWidth = (int)(maxWidth);
var newHeight = (int)(maxHeight);
var newImage = new Bitmap(newWidth, newHeight);
Graphics.FromImage(newImage).DrawImage(image, 0, 0, newWidth, newHeight);
Bitmap bmp = new Bitmap(newImage);
bmp.Save(Path.Combine(pathToThumbs, thumbname+"_resized.jpg"));
//File.Delete(Path.Combine(pathToThumbs, thumbname));
using (var engine = new Engine())
{
var conversionOptions = new ConversionOptions
{
VideoSize = VideoSize.Hd720,
AudioSampleRate = AudioSampleRate.Hz44100,
VideoAspectRatio = VideoAspectRatio.Default
};
engine.GetMetadata(inputPathVid);
engine.Convert(inputPathVid, outputPathVid, conversionOptions);
}
File.Delete(tempFilePath);
Video_Struct vd = new Video_Struct();
vd.CategoryID = 0; // store categoryname or term instead of category id
vd.Categories = "";
vd.UserName = model.username;
vd.Title = "";
vd.Description = "";
vd.Tags = "";
vd.Duration = inputPathVid.Metadata.Duration.ToString();
vd.Duration_Sec = Convert.ToInt32(inputPathVid.Metadata.Duration.Seconds.ToString());
vd.OriginalVideoFileName = model.fileName;
vd.VideoFileName = model.fileName;
vd.ThumbFileName = thumbname+"_resized.jpg";
vd.isPrivate = 0;
vd.AuthKey = "";
vd.isEnabled = 1;
vd.Response_VideoID = 0; // video responses
vd.isResponse = 0;
vd.isPublished = 1;
vd.isReviewed = 1;
vd.Thumb_Url = "none";
//vd.FLV_Url = flv_url;
vd.Embed_Script = "";
vd.isExternal = 0; // website own video, 1: embed video
vd.Type = 0;
vd.YoutubeID = "";
vd.isTagsreViewed = 1;
vd.Mode = 0; // filter videos based on website sections
//vd.ContentLength = f_contentlength;
vd.GalleryID = 0;
long videoid = VideoBLL.Process_Info(vd, false);
}`enter code here`