http web server return zip file in a windows phone 8 - windows-phone-8

Question

hello i'm write a http web server in my app.
I used this code
http://developer.nokia.com/community/wiki/A_simplistic_HTTP_Server_on_Windows_Phone
this procedure works but not have a extentions of file in http response
return a file name without extention (.zip)
private async Task<StringBuilder> HandleRequest(StreamSocket socket)
{
//Initialize IO classes
DataReader reader = new DataReader(socket.InputStream);
reader.InputStreamOptions = InputStreamOptions.Partial;
DataWriter writer = new DataWriter(socket.OutputStream);
writer.UnicodeEncoding = Windows.Storage.Streams.UnicodeEncoding.Utf8;
//handle actual HTTP request
String request = await StreamReadLine(reader);
string[] tokens = request.Split(' ');
if (tokens.Length != 3)
{
throw new Exception("invalid http request line");
}
string httpMethod = tokens[0].ToUpper();
string httpUrl = tokens[1];
//read HTTP headers - contents ignored in this sample
while (!String.IsNullOrEmpty(await StreamReadLine(reader))) ;
try
{
if (httpUrl == "DOWNLOADZIP")
{
using (IsolatedStorageFile storage = IsolatedStorageFile.GetUserStoreForApplication())
{
String content = null;
Stream stream;
byte[] data;
IsolatedStorageFileStream sri = storage.OpenFile("CompressedFiles.zip", FileMode.Open, FileAccess.Read);
if (null != sri)
{
stream = sri;
data = new byte[stream.Length];
stream.Read(data, 0, data.Length);
writer.writebytes(data);
}
}
}
}
catch (Exception ex)//any exception leads to an Internal server error
{
writer.WriteString("HTTP/1.0 500 Internal server error\r\n");
writer.WriteString("Connection: close\r\n");
writer.WriteString("\r\n");
writer.WriteString(ex.Message);
}
}
await writer.StoreAsync();//write data actually to the network interface
socket.Dispose();
return null;
}

Answer 1

this is a solutions
ret.AppendLine("HTTP/1.0 200 OK");
ret.AppendLine("Content-Type: text/html");
ret.AppendLine("Connection: close");
ret.AppendLine("");
ret.AppendLine("Content-Disposition: attachment; filename=myfile.zip");