如何用ASP上传一个大文件.带有进度条的.NET MVC4 Web Api
本文关键字：Api Web MVC4 NET 文件 ASP 何用 一个 | 更新日期: 2023-09-27 18:04:56
如何用ASP上传一个大文件?NET MVC4 Web Api
还能取得进步吗?
我看到了这篇文章，我明白如何处理上传的文件，但我如何才能获得进度数据?如何接受一个文件POST
请不要给我上传产品的链接我想了解如何处理这个在MVC4 Web Api的方式…这里是处理MVC4 WebApi中文件上传的示例代码
public async Task<HttpResponseMessage> Post()
{
if (Request.Content.IsMimeMultipartContent())
{
var path = HttpContext.Current.Server.MapPath("~/App_Data");
var provider = new MultipartFormDataStreamProvider(path);
await Request.Content.ReadAsMultipartAsync(provider).ContinueWith(t =>
{
if (t.IsFaulted || t.IsCanceled)
throw new HttpResponseException(HttpStatusCode.InternalServerError);
});
return Request.CreateResponse(HttpStatusCode.OK);
}
else
{
throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted"));
}
}
现在
await Request.Content.ReadAsMultipartAsync(provider)
我怎么能得到多少字节加载?
默认情况下上传到两个位置的文件大小是有限制的。一个在请求级别，第二个，如果您在IIS上托管，那么在web服务器级别。我添加了本博客中提到的几个配置，并且我能够上传一个36mb的文件而没有任何问题。我把这个片段贴在下面。
基本上1。
<system.web>
<httpRuntime maxRequestLength="2097152"/>
</system.web>
2。
<system.webServer>
<security>
<requestFiltering>
<requestLimits maxAllowedContentLength="2147483648" />
</requestFiltering>
</security><system.webServer>
如果你愿意，很容易找到加载到服务器的文件的大小。在你的代码
在读取流中的文件数据时，对于文件数据中的每个项，可以读取本地文件名，如下所示。
string savedFile = fileData.LocalFileName;
// use the file info class to derive properties of the uploaded file
FileInfo file = new FileInfo(savedFile);
//this will give the size of the uploaded file
long size = file.length/1024
希望这对你有帮助。我想知道为什么会降价?
我使用这个解决方案:
public class UploadController : ApiController
{
private static ConcurrentDictionary<string, State> _state = new ConcurrentDictionary<string, State>();
public State Get(string id)
{
State state;
if (_state.TryGetValue(id, out state))
{
return state;
}
return null;
}
public async Task<HttpResponseMessage> Post([FromUri] string id)
{
if (Request.Content.IsMimeMultipartContent())
{
var state = new State(Request.Content.Headers.ContentLength);
if (!_state.TryAdd(id, state))
throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.Conflict));
var path = System.Web.Hosting.HostingEnvironment.MapPath("~/App_Data");
var provider = new FileMultipartStreamProvider(path, state.Start, state.AddBytes);
await Request.Content.ReadAsMultipartAsync(provider).ContinueWith(t =>
{
_state.TryRemove(id, out state);
if (t.IsFaulted || t.IsCanceled)
throw new HttpResponseException(HttpStatusCode.InternalServerError);
});
return Request.CreateResponse(HttpStatusCode.OK);
}
else
{
throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted"));
}
}
}
public class State
{
public long? Total { get; set; }
public long Received { get; set; }
public string Name { get; set; }
public State(long? total = null)
{
Total = total;
}
public void Start(string name)
{
Received = 0;
Name = name;
}
public void AddBytes(long size)
{
Received = size;
}
}
public class FileMultipartStreamProvider : MultipartStreamProvider
{
private string _rootPath;
private Action<string> _startUpload;
private Action<long> _uploadProgress;
public FileMultipartStreamProvider(string root_path, Action<string> start_upload, Action<long> upload_progress)
: base()
{
_rootPath = root_path;
_startUpload = start_upload;
_uploadProgress = upload_progress;
}
public override System.IO.Stream GetStream(HttpContent parent, System.Net.Http.Headers.HttpContentHeaders headers)
{
var name = (headers.ContentDisposition.Name ?? "undefined").Replace("'"", "").Replace("''", "_").Replace("/", "_").Replace("..", "_");
_startUpload(name);
return new WriteFileStreamProxy(Path.Combine(_rootPath, name), _uploadProgress);
}
}
public class WriteFileStreamProxy : FileStream
{
private Action<long> _writeBytes;
public WriteFileStreamProxy(string file_path, Action<long> write_bytes)
: base(file_path, FileMode.Create, FileAccess.Write)
{
_writeBytes = write_bytes;
}
public override void EndWrite(IAsyncResult asyncResult)
{
base.EndWrite(asyncResult);
#if DEBUG
System.Threading.Thread.Sleep(100);
#endif
if (_writeBytes != null)
_writeBytes(base.Position);
}
public override void Write(byte[] array, int offset, int count)
{
base.Write(array, offset, count);
#if DEBUG
System.Threading.Thread.Sleep(100);
#endif
if (_writeBytes != null)
_writeBytes(base.Position);
}
}
和非缓冲输入流的小配置:
config.Services.Replace(typeof(IHostBufferPolicySelector), new CustomPolicy());
实现:
public class CustomPolicy : System.Web.Http.WebHost.WebHostBufferPolicySelector
{
public override bool UseBufferedInputStream(object hostContext)
{
return false;
}
}
我最终使用了一个HttpModule，但即使是HttpModule也不会显示进度条我发现了一些非常有趣的事情，似乎当我在安全协议(https://))上上传文件时，进度正在工作，但在非安全协议(http://))上，进度不工作，文件被完全缓冲，我不知道的方式是这样的，我相信这是IIS到Asp.net框架之间的某个bug当请求得到处理时。
现在，因为我成功地使它工作在https与HttpModule，我相信这是有可能使它工作也与Mvc Web Api，但我目前没有时间去检查。
用于解析多部分表单数据，我使用Nancy HttpMultipart解析器:https://github.com/NancyFx/Nancy/tree/master/src/Nancy只是抓取类:
HttpMultipart.cs
HttpMultipartBoundary.cs
HttpMultipartBuffer.cs
HttpMultipartSubStream.cs
这里是HttpModule来源:
public class HttpUploadModule : IHttpModule
{
public static DateTime lastClean = DateTime.UtcNow;
public static TimeSpan cleanInterval = new TimeSpan(0,10,0);
public static readonly object cleanLocker = new object();
public static readonly Dictionary<Guid,UploadData> Uploads = new Dictionary<Guid,UploadData>();
public const int KB = 1024;
public const int MB = KB * 1024;
public static void CleanUnusedResources( HttpContext context)
{
if( lastClean.Add( cleanInterval ) < DateTime.UtcNow ) {
lock( cleanLocker )
{
if( lastClean.Add( cleanInterval ) < DateTime.UtcNow )
{
int maxAge = int.Parse(ConfigurationManager.AppSettings["HttpUploadModule.MaxAge"]);
Uploads.Where(u=> DateTime.UtcNow.AddSeconds(maxAge) > u.Value.createdDate ).ToList().ForEach(u=>{
Uploads.Remove(u.Key);
});
Directory.GetFiles(context.Server.MapPath(ConfigurationManager.AppSettings["HttpUploadModule.Folder"].TrimEnd('/'))).ToList().ForEach(f=>{
if( DateTime.UtcNow.AddSeconds(maxAge) > File.GetCreationTimeUtc(f)) File.Delete(f);
});
lastClean = DateTime.UtcNow;
}
}
}
}
public void Dispose()
{
}
public void Init(HttpApplication app)
{
app.BeginRequest += app_BeginRequest;
}
void app_BeginRequest(object sender, EventArgs e)
{
HttpContext context = ((HttpApplication)sender).Context;
Guid uploadId = Guid.Empty;
if (context.Request.HttpMethod == "POST" && context.Request.ContentType.ToLower().StartsWith("multipart/form-data"))
{
IServiceProvider provider = (IServiceProvider)context;
HttpWorkerRequest wr = (HttpWorkerRequest)provider.GetService(typeof(HttpWorkerRequest));
FileStream fs = null;
MemoryStream ms = null;
CleanUnusedResources(context);
string contentType = wr.GetKnownRequestHeader(HttpWorkerRequest.HeaderContentType);
NameValueCollection queryString = HttpUtility.ParseQueryString( wr.GetQueryString() );
UploadData upload = new UploadData { id = uploadId ,status = 0, createdDate = DateTime.UtcNow };
if(
!contentType.Contains("boundary=") ||
/*AT LAST 1KB */ context.Request.ContentLength < KB ||
/*MAX 5MB */ context.Request.ContentLength > MB*5 ||
/*IS UPLOADID */ !Guid.TryParse(queryString["upload_id"], out uploadId) || Uploads.ContainsKey( uploadId )) {
upload.id = uploadId;
upload.status = 2;
Uploads.Add(upload.id, upload);
context.Response.StatusCode = 400;
context.Response.StatusDescription = "Bad Request";
context.Response.End();
}
string boundary = Nancy.HttpMultipart.ExtractBoundary( contentType );
upload.id = uploadId;
upload.status = 0;
Uploads.Add(upload.id, upload);
try {
if (wr.HasEntityBody())
{
upload.bytesRemaining =
upload.bytesTotal = wr.GetTotalEntityBodyLength();
upload.bytesLoaded =
upload.BytesReceived = wr.GetPreloadedEntityBodyLength();
if (!wr.IsEntireEntityBodyIsPreloaded())
{
byte[] buffer = new byte[KB * 8];
int readSize = buffer.Length;
ms = new MemoryStream();
//fs = new FileStream(context.Server.MapPath(ConfigurationManager.AppSettings["HttpUploadModule.Folder"].TrimEnd('/')+'/' + uploadId.ToString()), FileMode.CreateNew);
while (upload.bytesRemaining > 0)
{
upload.BytesReceived = wr.ReadEntityBody(buffer, 0, readSize);
if(upload.bytesRemaining == upload.bytesTotal) {
}
ms.Write(buffer, 0, upload.BytesReceived);
upload.bytesLoaded += upload.BytesReceived;
upload.bytesRemaining -= upload.BytesReceived;
if (readSize > upload.bytesRemaining)
{
readSize = upload.bytesRemaining;
}
}
//fs.Flush();
//fs.Close();
ms.Position = 0;
//the file is in our hands
Nancy.HttpMultipart multipart = new Nancy.HttpMultipart(ms, boundary);
foreach( Nancy.HttpMultipartBoundary b in multipart.GetBoundaries()) {
if(b.Name == "data") {
upload.filename = uploadId.ToString()+Path.GetExtension( b.Filename ).ToLower();
fs = new FileStream(context.Server.MapPath(ConfigurationManager.AppSettings["HttpUploadModule.Folder"].TrimEnd('/')+'/' + upload.filename ), FileMode.CreateNew);
b.Value.CopyTo(fs);
fs.Flush();
fs.Close();
upload.status = 1;
context.Response.StatusCode = 200;
context.Response.StatusDescription = "OK";
context.Response.Write( context.Request.ApplicationPath.TrimEnd('/') + "/images/temp/" + upload.filename );
}
}
}
}
}
catch(Exception ex) {
upload.ex = ex;
}
if(upload.status != 1)
{
upload.status = 2;
context.Response.StatusCode = 400;
context.Response.StatusDescription = "Bad Request";
}
context.Response.End();
}
}
}
public class UploadData {
public Guid id { get;set; }
public string filename {get;set;}
public int bytesLoaded { get; set; }
public int bytesTotal { get; set; }
public int BytesReceived {get; set;}
public int bytesRemaining { get;set; }
public int status { get;set; }
public Exception ex { get;set; }
public DateTime createdDate { get;set; }
}