How to use 4 background workers to show upload status - C# Discussion Boards

Re: How to use 4 background workers to show upload status

10-Jul-09 3:12

Hi,

I have an application in which I want to upload some values, signatures and photos to the server.I want to show 4 progress bars. Some values, signatures and photos upload status on their own progress bar. 4th progress bar will show the status of all above 3 uploads collectively.

I am posting a method where I have code for it.

private void UploadServiceValuesPhotosAndSignature()
{
bool[] allResponses;
List<signature> signatures = null;

foreach (var serviceInstance in serviceInstances)
{
//Get All Signatures
signatures = serviceValues.Select(sv => sv.Signature).Distinct().ToList();

//Get All Photos
allPhotosToUpload = PostPhotoCollection.GetPhotos(serviceInstance, context);
int count = allPhotosToUpload.Count + signatures.Count + 1;
allResponses = new bool[count];

int i = 0;

//Upload serviceValues
serviceValuesWorker = new BackgroundWorker();
serviceValuesWorker.WorkerReportsProgress = true;
serviceValuesWorker.WorkerSupportsCancellation = true;

serviceValuesWorker.DoWork += delegate(object s, DoWorkEventArgs args)
{
serviceValuesWorker.ReportProgress(10);
if (serviceValuesWorker.CancellationPending)
{
args.Cancel = true;
return;
}
serviceValuesWorker.ReportProgress(50);

//serviceValuesWorker doing its work

var serializableValues = serviceInstance.ServiceValues.AsSerializable();
var serialisedValues = new Dictionary<string, object[]=""> { { "ValuesInfo", serializableValues } }.Serialize();
string responseFromServer = ServiceRequest.GetResponse("UpdateServiceInstanceMobile", "ServiceInstances", serialisedValues, serviceInstance.ServiceInstanceID.ToString());
var response = responseFromServer.Deserialize<dictionary<string, object="">>();
bool successServiceValues = (bool)response["success"];
if (successServiceValues)
{
serviceValuesWorker.ReportProgress(100);
}
args.Result = successServiceValues;
};
serviceValuesWorker.ProgressChanged += delegate(object s, ProgressChangedEventArgs args)
{
serviceValuesProgressBar.Value = args.ProgressPercentage;
};
serviceValuesWorker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args)
{
//serviceValuesWorker modifying the allResponses array
allResponses[i++] = (bool) args.Result;

};
serviceValuesWorker.RunWorkerAsync();

//Upload Signatures
signatureWorker = new BackgroundWorker();
signatureWorker.WorkerReportsProgress = true;
signatureWorker.WorkerSupportsCancellation = true;

signatureWorker.DoWork += delegate(object s, DoWorkEventArgs args)
{
signatureWorker.ReportProgress(10);
if (signatureWorker.CancellationPending)
{
args.Cancel = true;
return;
}
signatureWorker.ReportProgress(50);

//signatureWorker doing its work

bool[] responseArray = new bool[signatures.Count];
int j = 0;
foreach (var signature in signatures)
{
string signaturePath = signature.SignaturePath;
byte[] signatureByteArray = SignatureFileConversion.SignatureFileToByteArray(signaturePath);
string signatureToUpload = signatureByteArray.Serialize();
var signatureResponseFromServer = ServiceRequest.GetSignatureResponse("AddSignature", "ServiceInstances", serviceValuesString, serviceInstance.ServiceInstanceID.ToString(), signatureToUpload);
var signatureResponse = signatureResponseFromServer.Deserialize<dictionary<string, object="">>();
responseArray[j++] = (bool)signatureResponse["success"];
}
}
if(!responseArray.Contains(false))
{
signatureWorker.ReportProgress(100);
}
args.Result = responseArray;
};
signatureWorker.ProgressChanged += delegate(object s, ProgressChangedEventArgs args)
{
signatureProgressBar.Value = args.ProgressPercentage;
};
signatureWorker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args)
{
bool[] signatureResponses = (bool[]) args.Result;
foreach (var response in signatureResponses)
{
//modifying the allResponses array

allResponses[i++] = response;
}

};
signatureWorker.RunWorkerAsync();

//Upload Photos
photoWorker = new BackgroundWorker();
photoWorker.WorkerReportsProgress = true;
photoWorker.WorkerSupportsCancellation = true;

photoWorker.DoWork += delegate(object s, DoWorkEventArgs args)
{
photoWorker.ReportProgress(10);
if (photoWorker.CancellationPending)
{
args.Cancel = true;
return;
}
photoWorker.ReportProgress(50);

//photoWorker doing its work

bool[] photoResponseArray = new bool[allPhotosToUpload.Count];
int k = 0;
foreach (var photo in allPhotosToUpload)
{
photoResponseArray[k++] = PostPhotoCollection.SendPhoto(photo);
}
if(!photoResponseArray.Contains(false))
{
photoWorker.ReportProgress(100);
}
args.Result = photoResponseArray;
};
photoWorker.ProgressChanged += delegate(object s, ProgressChangedEventArgs args)
{
serviceValuesProgressBar.Value = args.ProgressPercentage;
};
photoWorker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args)
{
bool[] photoResponses = (bool[]) args.Result;
foreach (var response in photoResponses)
{
allResponses[i++] = response;
}

};
photoWorker.RunWorkerAsync();

//Update main ProgressBar
mainWorker = new BackgroundWorker();
mainWorker.WorkerReportsProgress = true;
mainWorker.WorkerSupportsCancellation = true;

mainWorker.DoWork += delegate(object s, DoWorkEventArgs args)
{
mainWorker.ReportProgress(10);
if (mainWorker.CancellationPending)
{
args.Cancel = true;
return;
}
mainWorker.ReportProgress(50);

//mainWorker doing its work
if (!allResponses.Contains(false))
{
bool IsDone = true;
string finalResponseFromServer = ServiceRequest.GetFinalResponse("SubmitChanges", "ServiceInstances", IsDone.ToString(), serviceInstance.ServiceInstanceID.ToString(), allPhotosToUpload.Count.ToString(), signatures.Count().ToString());
var finalResponse = finalResponseFromServer.Deserialize<dictionary<string, object="">>();
finalSuccessMessage = (bool)finalResponse["success"];
args.Result = finalSuccessMessage;
if (finalSuccessMessage)
{
mainWorker.ReportProgress(100);
}
}
};
mainWorker.ProgressChanged += delegate(object s, ProgressChangedEventArgs args)
{
mainProgressBar.Value = args.ProgressPercentage;
};
mainWorker.RunWorkerCompleted += delegate(object s, RunWorkerCompletedEventArgs args)
{
btnClose.IsEnabled = true;

};
mainWorker.RunWorkerAsync();

}
}

I am getting AccessViolation exception, and the array allResponses is not modified at all.
I know the result of DoWork event can be accessed in RunCompleted event, then why allResponses array is not modifying.

Thanks for reading I know the code block is too long.

MumbleB10-Jul-09 3:54

MumbleB

10-Jul-09 3:54

I would declare 1 delegate for ShowProgress. Something like the below:

public delegate void ShowProgress(ProgressBar progressbar, int prg);

private void showProgress(ProgressBar progressbar, int prg)
{
    if (this.WindowState == FormWindowState.Minimized)
        return;

    if (progressbar.InvokeRequired)
        progressbar.BeginInvoke(new ShowProgress(showProgress), new object[] { progressbar, prg });

    else
    {
        if (prg < progressbar.Maximum)
            progressbar.Value = prg;

        else
            progressbar.Value = progressbar.Maximum;
    }
}

Then call the progressbar in each worker.

showProgress(progressBar1, 100);

I think this should work.

Excellence is doing ordinary things extraordinarily well.

Re: How to use 4 background workers to show upload status

vsaratkar10-Jul-09 4:15

Re: How to use 4 background workers to show upload status

10-Jul-09 4:15

Thanks ,
I will give it a try.

Thanks again.

vsaratkar10-Jul-09 5:19

Re: How to use 4 background workers to show upload status

10-Jul-09 5:19

Sorry I tried delegates to update progress bar, but got the same exception "AccessViolation".

Thanks,

MumbleB10-Jul-09 6:46

MumbleB

10-Jul-09 6:46

What is the full message? If you post the full error message I might be able to help a bit more. I suppose that it is trying to access something outside the Thread that it was called on? Can you post the full error message?

Are you using VS2005 or VS2008? Does the code actually compile? When I try to compile the code I get numerous errors i.e. Expression errors etc.

Excellence is doing ordinary things extraordinarily well.

Re: How to use 4 background workers to show upload status

vsaratkar10-Jul-09 7:21

how to build a receipt number

10-Jul-09 7:21

Thanks for all your help,

This is the runtime exception I am getting "AccessViolationException".
"Attempted to read or write protected memory. This is often an indication that other memory is corrupt."

My code does compile. I just trimmed it down since it will be too long.
As far as I know about backgroundWorker, in DoWork event args.Result stores the result of long running process.
And this result is available in RunCompleted event as args.Result.

In my case the array allResponses is not modifying at all after the work is done. I have to modify that array in all three long running processes.

I am using VS2008. My upload is working perfectly fine without progressBars and threads.

I think there is some locking issue.

Thanks,

kKamel10-Jul-09 2:50

10-Jul-09 2:50

Hello there i need to build a receipt number the values that am receiveing is this

RecieptCode LastRecieptNumber RecieptDisplayDigits
Rcp2008- 248 8

now the main prob is in receipdisplayDigits

i know in python if i write z*8 it will be zzzzzzzz
i want the same thing in C# but if i did it i will not be able to add the last reciept number/

how could this be done?
i have another method but am sure there would be a better one my method is to add the lastreceiptnumber
with 10^(receipt display digt) then i remove the 1 and write the receipt code it will look like this

the example above
10^8 = 100000000
100000000 + 249 (since it should be new receipt) = 100000249
Convert it to string and remove the 1 = 00000249
Then i add the receipt code

Is there better way taking into concideration the performance

Best Regards

kKamel10-Jul-09 2:58

10-Jul-09 2:58

The reciept will be Rcp2008-00000249

please note that the receipt code is Rcp2008-
receiptLat number is 248
diplay digits is 8

Mirko198010-Jul-09 3:01

Mirko1980

10-Jul-09 3:01

If I understood correctly, you can do like this:

string receiptCode = "Rcp2008";
int lastReceiptNumber = 248;
int receiptDisplayDigits = 8;

string receiptString = lastReceiptNumber.ToString().PadLeft(receiptDisplayDigits, '0');
string fullReceiptCode = string.Format("{0}-{1}", receiptCode, receiptString);

EDIT: expanded taking into account your second post.

kKamel10-Jul-09 3:23

10-Jul-09 3:23

it worked fine but i did not understand the last line of code could you explain it please??

Mirko198010-Jul-09 3:36

Mirko1980

10-Jul-09 3:36

string receiptString = lastReceiptNumber.ToString().PadLeft(receiptDisplayDigits, '0');

This line converts lastReceiptNumber to string, then adds as many 0 at its left as it's needed to have a string receiptDisplayDigits characters long.
You cas also do as musefan suggested and use receiptString = lastReceiptNumber.ToString("D" + receiptDisplayDigits); instead.
After this line, receiptString will be 00000249.

string fullReceiptCode = string.Format("{0}-{1}", receiptCode, receiptString);

This line will concatenate the string created in the first line with receiptCode, using a template to define the string format.
You can also use a direct string concatenation (string fullReceiptCode = receiptCode + "-" + receiptString;).
After this line, fullReceiptCode will be Rcp2008-00000249.

kKamel10-Jul-09 3:39

10-Jul-09 3:39

Ahh ok ok man thanks alot i knew this but i forgot it because its been a while since i used {0} {1}... Big Grin | :-D

kKamel10-Jul-09 3:55

10-Jul-09 3:55

It did not work the thing you wrote about padding left since when i convert to int
the 0000000000 will turn into 0

but thanks you gave me an answer about the padding thing Big Grin | :-D

Mirko198010-Jul-09 4:08

Mirko1980

10-Jul-09 4:08

That's right, the padding is related to strings, if you convert back the string to int, you will lose al format you have applied to it.

musefan10-Jul-09 3:18

musefan

10-Jul-09 3:18

I really like the logic you have used in getting a value with 8 digits, it's great to see people thinking along those lines rather than expecting things to be done with a simple 'out the box' line of code (and thus never really learning how things are actually acheived).

But in instances like this one-liners are the way to go, so hope this helps...

int newNumber = lastReceiptNumber + 1;
string displayNumber = newNumber.ToString("D" + receiptDisplayDigits);

Life goes very fast. Tomorrow, today is already yesterday.

kKamel10-Jul-09 3:37

10-Jul-09 3:37

Thanks man i really appreciate it, we ask question so we could learn how to solve them other wise we are not programers we are just people who ask questions

musefan10-Jul-09 4:07

musefan

10-Jul-09 4:07

Exactly, and questions like yours will always be welcome in The Code Project forums Wink | ;)

Life goes very fast. Tomorrow, today is already yesterday.

kKamel10-Jul-09 3:53