C#: My callback function gets called twice for every Sent Request
- by Madi D.
I've Got a program that uploads/downloads files into an online server,Has a callback to report progress and log it into a textfile, The program is built with the following structure:
public void Upload(string source, string destination)
{
//Object containing Source and destination to pass to the threaded function
KeyValuePair<string, string> file = new KeyValuePair<string, string>(source, destination);
//Threading to make sure no blocking happens after calling upload Function
Thread t = new Thread(new ParameterizedThreadStart(amazonHandler.TUpload));
t.Start(file);
}
private void TUpload(object fileInfo)
{
KeyValuePair<string, string> file = (KeyValuePair<string, string>)fileInfo;
/*
Some Magic goes here,Checking The file and Authorizing Upload
*/
var ftiObject = new FtiObject ()
{ FileNameOnHDD = file.Key,
DestinationPath = file.Value,
//Has more data used for calculations.
};
//Threading to make sure progress gets callback gets called.
Thread t = new Thread(new ParameterizedThreadStart(amazonHandler.UploadOP));
t.Start(ftiObject);
//Signal used to stop progress untill uploadCompleted is called.
uploadChunkDoneSignal.WaitOne();
/*
Some Extra Code
*/
}
private void UploadOP(object ftiSentObject)
{
FtiObject ftiObject = (FtiObject)ftiSentObject;
/*
Some useless code to create the uri and prepare the ftiObject.
*/
// webClient.UploadFileAsync will open a thread that
// will upload the file and report
// progress/complete using registered callback functions.
webClient.UploadFileAsync(uri, "PUT", ftiObject.FileNameOnHDD, ftiObject);
}
I got a callback that is registered to the Webclient's UploadProgressChanged event , however it is getting called twice per sent request.
void UploadProgressCallback(object sender, UploadProgressChangedEventArgs e)
{
FtiObject ftiObject = (FtiObject )e.UserState;
Logger.log(ftiObject.FileNameOnHDD, (double)e.BytesSent ,e.TotalBytesToSend);
}
Log Output:
Filename: C:\Text1.txt Uploaded:1024 TotalFileSize: 665241
Filename: C:\Text1.txt Uploaded:1024 TotalFileSize: 665241
Filename: C:\Text1.txt Uploaded:2048 TotalFileSize: 665241
Filename: C:\Text1.txt Uploaded:2048 TotalFileSize: 665241
Filename: C:\Text1.txt Uploaded:3072 TotalFileSize: 665241
Filename: C:\Text1.txt Uploaded:3072 TotalFileSize: 665241
Etc...
I am watching the Network Traffic using a watcher, and only 1 request is being sent.
Some how i cant Figure out why the callback is being called twice, my doubt was that the callback is getting fired by each thread opened(the main Upload , and TUpload), however i dont know how to test if thats the cause.
Note: The reason behind the many /**/ Comments is to indicate that the functions do more than just opening threads, and threading is being used to make sure no blocking occurs (there a couple of "Signal.WaitOne()" around the code for synchronization)
