public TestController(IOptions <BigFileFormOptions> options, IHostEnvironment env,
ILogger <TestController> logger)
{
_options = options.Value;
_baseDirectory = env.ContentRootPath;
_logger = logger;
}
public static async Task <RequestForms> ExtractFormAsync(this HttpRequest request,
BigFileFormOptions options,
Func <string, string, FileStream> nameFiles)
{
if (!MultipartRequestHelper.IsMultipartContentType(request.ContentType) || !request.HasFormContentType)
{
throw new UnsupportedContentTypeException("unsupported content type");
}
if (!HttpMethods.IsPost(request.Method) && !HttpMethods.IsPut(request.Method))
{
throw new NotSupportedException("only POST or PUT methods are allowed");
}
//允许Request.Body多次读取
request.EnableBuffering();
var texts = new Dictionary <string, string>();
var files = new Dictionary <string, string>();
var errors = new Dictionary <string, string>();
var boundary = MultipartRequestHelper.GetBoundary(
MediaTypeHeaderValue.Parse(request.ContentType));
var reader = new MultipartReader(boundary, request.Body);
try
{
MultipartSection section;
while ((section = await reader.ReadNextSectionAsync()) != null)
{
var hasContentDispositionHeader =
ContentDispositionHeaderValue.TryParse(
section.ContentDisposition, out var contentDisposition);
if (!hasContentDispositionHeader)
{
continue;
}
if (!MultipartRequestHelper
.HasFileContentDisposition(contentDisposition))
{
texts[contentDisposition.Name.Value.ToLower()] = await section.ReadAsStringAsync();
}
else
{
var key = contentDisposition.Name.Value;
var fileName = contentDisposition.FileName.Value;
var ext = Path.GetExtension(fileName);
if (!options.PermittedExtensions.Contains(ext))
{
errors[key] = $"'{ext}' is disallowed to upload";
continue;
}
await using var stream = nameFiles(key, fileName);
if (!stream.CanWrite)
{
throw new Exception("the file stream cannot write");
}
var buffer = new byte[2 * 1024 * 1024];
int bufferLength;
while ((bufferLength = await section.Body.ReadAsync(buffer, 0, buffer.Length)) > 0)
{
await stream.WriteAsync(buffer, 0, bufferLength);
}
if (stream.Length > options.FileSizeLimit)
{
File.Delete(stream.Name);
errors[key] = $"{fileName} is oversize";
continue;
}
files[key] = stream.Name;
}
}
return(new RequestForms(texts, files, errors));
}
catch (IOException)
{
const string msg = "failed to upload.try recheck the file";
throw new IOException(msg);
}
}
