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我有一個位於網頁上的Silverlight應用程序。它允許用戶將多個文檔上傳到服務器。當我開始上傳一個文件到服務器,我會做出一個處理程序的調用一個POST請求,我把它塊,如果該文件是太大用下面的代碼:Silverlight從處理程序接收響應
private void UploadFileEx()
{
Status = FileUploadStatus.Uploading;
var temp = FileLength - BytesUploaded;
var ub = new UriBuilder(_urlServer);
var complete = temp <= ChunkSize;
ub.Query = string.Format("{3}locationCode={4}&filename={0}&StartByte={1}&Complete={2}", RockDocumentName, BytesUploaded, complete,
string.IsNullOrEmpty(ub.Query) ? string.Empty : string.Format("{0}&", ub.Query.Remove(0, 1)), _locationCode);
var webrequest = (HttpWebRequest) WebRequest.Create(ub.Uri);
webrequest.Method = "POST";
// Begins an asynchronous request for a Stream object to use to write data.
// The asynchronous callback method uses the EndGetRequestStream method to return the actual stream.
// This means
webrequest.BeginGetRequestStream(WriteCallback, webrequest);
}
private void WriteCallback(IAsyncResult asynchronousResult)
{
var webrequest = (HttpWebRequest) asynchronousResult.AsyncState;
// End the operation.
// Here we obtain the stream to write the request
var requestStream = webrequest.EndGetRequestStream(asynchronousResult);
var buffer = new Byte[4096];
int bytesRead;
var tempTotal = 0;
Stream fileStream = File.OpenRead();
fileStream.Position = BytesUploaded;
while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0 && tempTotal + bytesRead < ChunkSize)
{
requestStream.Write(buffer, 0, bytesRead);
requestStream.Flush();
BytesUploaded += bytesRead;
tempTotal += bytesRead;
if (UploadProgressChanged != null)
{
var percent = (int) ((BytesUploaded/(double) FileLength)*100);
var args = new UploadProgressChangedEventArgs(percent, bytesRead, BytesUploaded, FileLength,
RockDocumentName);
Dispatcher.BeginInvoke(() => UploadProgressChanged(this, args));
}
}
fileStream.Close();
requestStream.Close();
// Whenever the operation is ready call the ReadCallback method (when this method
// is called we know that the chunk of file has arrived successfully to the server,
// it's time to process the next chunk).
webrequest.BeginGetResponse(ReadCallback, webrequest);
}
我想我的處理程序返回我的文檔名稱(我爲處理程序中的每個文檔生成一個新文件名,因爲我們有一個正在使用的文檔命名標準)。所以,我編寫我的AsyncCallback這樣,我期待的AsyncState會回到我以爲我settting在處理器頭:
private void ReadCallback(IAsyncResult asynchronousResult)
{
var documentName = ((System.Net.BrowserHttpWebRequest)asynchronousResult.AsyncState).Headers["documentname"].ToString();
if (BytesUploaded < FileLength)
UploadFileEx();
else
{
Status = FileUploadStatus.Complete;
}
}
這裏是我的處理程序:
public void ProcessRequest(HttpContext context) {
Context = context;
UploadFile();
//context.Request.Headers.Add("documentname", "testfilename.pdf");
context.Response.Headers.Add("documentname", "testfilename.pdf");
}
這不是工作正如我原先想的那樣。我究竟做錯了什麼?我是否在我的處理程序中設置了錯誤標題?我的處理程序是否有另一種方式與Silverlight客戶端應用程序交談?
任何幫助,將不勝感激。提前致謝!
感謝,這工作!從另一天把我的頭靠在桌子上,挽救了我。 – Mark 2011-04-18 14:47:58