Re: Multi-threading - Parallel Syncronization - C# Discussion Boards

Re: Adhoc networking using windows application in VS2005

31-Mar-09 5:12

As Ceaser once said.... Thumbs Down | :thumbsdown:

(now where are my damn lions Laugh | :laugh:

)

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

alish061031-Mar-09 20:17

alish0610

31-Mar-09 20:17

Hi dude i just dint got what u mean to say ...
i am using managed wifi library to do this project , and
this is the link where you can find this library ...

http://managedwifi.codeplex.com/
u may get some idea what i want ....

Thanks for ur time and reply...

OpenFileDialog

netJP12L31-Mar-09 4:22

netJP12L

31-Mar-09 4:22

How can i hide from OpenFileDialog the "Look in" from the top and Recent, Desktop, My Documents,My Computer and My Network options?

I d'nt want user to Browse a folder from a specific location
Thanks

Re: OpenFileDialog

musefan31-Mar-09 4:30

c# 2005 add_In Excel 2003

31-Mar-09 4:30

Im almost certain that it is not possible with the OpenFileDialog control. You would prob be best to create your own control to browse files.

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

Re: OpenFileDialog

Giorgi Dalakishvili31-Mar-09 4:39

Giorgi Dalakishvili

31-Mar-09 4:39

This links should help:

Customize Your Open File Dialog[^]

Extend the Common Dialog Boxes Using Windows Forms 1.x[^]

Windows Vista for Developers – Part 6 – The New File Dialogs [^]

Giorgi Dalakishvili

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My Articles

Asynchronous Registry Notification Using Strongly-typed WMI Classes in .NET [^]

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sofianeannabi31-Mar-09 4:13

sofianeannabi

31-Mar-09 4:13

Salam

with Add-in installation and setup information
to automatise Excel ,I can't create new NamedRange
in methode public void OnConnection(object application, Extensibility.ext_ConnectMode connectMode, object addInInst, ref System.Array custom)

or to cast Microsoft.Office.Interop.Excel.WorkSheet to
Microsoft.Office.Tools.Excel.WorkSheet

Thanks D'Oh! | :doh:

good day for all

Multi-threading - Parallel Syncronization

caksabre231-Mar-09 4:12

caksabre2

31-Mar-09 4:12

Hello,

I have a program that opens multiple user controls, each one needing to run 3 parallel processes. It needs to run all 3 simultaneously, and then when all 3 are complete run a process. This needs to occur every second.

What I have done, is create 3 threads, one main thread which when it starts running it calls two .Set() methods for manualevent handlers which then sets the other two threads running. I then have a waitall in the main thread (after the point where it has done its work) which waits for the other two threads to complete. At the end of the two threads I have a waitall which waits for a different manualevent to be reset (which happens when the main thread finishes).

Now this all seems to work fine, but when running 4 user controls at once, approximetly every minute the threads somehow get confused and one of the waitall's for the two sub threads get stuck. So I have put a timeout parameter here which is a hack, and doesn't really solve why it is locking up. I can't put all the code in but below is an example of it working.

Can anyone help come up with why this is occurring, or a better way of doing this?

//Thread Ones Run Method
public void ThreadOne()
{
while(true)
{

ogEvents[0] = new ManualResetEvent(false);
ogEvents[1] = new ManualResetEvent(false);

//Do a task here
//Wait for the other 2 threads to finish
bool blSuccess = WaitHandle.WaitAll(ogEvents, 4000, false);

//Do some calcs

Thread.Sleep(1000);
ogThreadTwo[0].Set();
ogThreadThree[0].Set();
}
}

//Thread Two's Run Method
public void ThreadTwo()
{
while(true)
{
//Do some task
//Task Finished
ogEvents[0].Set();
ogThreadTwo[0] = new ManualResetEvent(false);
bool blSuccess = WaitHandle.WaitAll(ogThreadTwo, 4000, false);
}
}

//Thread Three's Run Method
public void ThreadThree()
{
while(true)
{
//Do some task

//Task Finished
ogEvents[0].Set();
ogThreadThree[0] = new ManualResetEvent(false);
bool blSuccess = WaitHandle.WaitAll(ogThreadThree, 4000, false);
}
}

Luc Pattyn31-Mar-09 4:54

Luc Pattyn

31-Mar-09 4:54

Hi,

why are you creating new ManualResetEvents all the time? I would create them once, and resuse them, i.a. call Set(), Reset() and Wait/WaitAll() as required, no more no less. Replacing one ManualResetEvent by another you are risking signaling or waitinf for one that isn't actually in business any more.

Whatever you do, you must allow for any or all of your threads not to get any CPU cycles at all for some time, e.g. because some high-priority thing suddenly happens.

Smile | :)

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Ian Shlasko31-Mar-09 5:02

Ian Shlasko

31-Mar-09 5:02

Purely for organizational purposes, I would actually have a fourth thread controlling the other three, if possible. Threading problems can be difficult to debug, so keeping the code clean can sometimes be a big help...

Also, I would probably go with just basic EventWaitHandles

EventWaitHandle workerThreadStart[] = new EventWaitHandle[3];
EventWaitHandle workerThreadFinish[] = new EventWaitHandle[3];

// Controller thread:

while (true)
{
  for (int x = 0; x < 3; x++) workerThreadStart[x].Set();
  WaitHandle.WaitAll(workerThreadFinish);

  // Insert a delay if desired
}

// Each worker thread (# = 0, 1, or 2 for threads one, two, three):

while (true)
{
  workerThreadStart[#].WaitOne();

  try
  {
    // Do some task
  }
  catch (...)
  {
    // Remember, if you get an exception on a background thread, it may not display
  }
  finally 
  {
    // Even if we get an error, we want to set the EWH so as not to stall everything
    workerThreadFinish[#].Set();
  }
}

(Note: Just typed this out in here, not in a code editor, so might have typos or syntax problems - Just trying to give a rough idea anyway)

EDIT: Oh, and when you instantiate the EWH's, bring 'em up unsignaled and AutoReset.

Alan N31-Mar-09 5:17

Alan N

31-Mar-09 5:17

Hi,
I'm not sure why you are continually reallocating the event objects. Doing so may have created a situation where you are waiting for a signal on an event object that is no longer referenced in your code.

It is quite possible that ThreadOne could set ogThreadTwo or ogThreadThree prior to reallocation in ThreadTwo or ThreadThree. If that happens the WaitAll methods will block as they are waiting for the reallocated events to be signalled.

//Task Finished
ogEvents[0].Set();
ogThreadThree[0] = new ManualResetEvent(false);
bool blSuccess = WaitHandle.WaitAll(ogThreadThree, 4000, false);

should be reordered

ogThreadThree[0] = new ManualResetEvent(false);
ogEvents[0].Set();
bool blSuccess = WaitHandle.WaitAll(ogThreadThree, 4000, false);

so that ogThreadThree event is rellocated BEFORE you release ThreadOne.

Alan.

why button_click event raising 2 times?

caksabre231-Mar-09 5:37

caksabre2

31-Mar-09 5:37

Thanks for the reply's. I have changed the code to have 4 threads, and have stopped reallocating the event and it seems to have fixed any sync issues.

Thanks

Narendra Reddy Vajrala31-Mar-09 3:43

31-Mar-09 3:43

Hi all,
in my C#.net 3.5 windows application, i have a insert statement in my button_Click event.
but this is raising 2 times, so 2 rows with same data inserting instead of 1.
i checked in debugmode after reaching last statement it is moving to first statement again.
why this is happening?

Please give some solution

Thanks in Advance
--Naren
Blush | :O

stancrm31-Mar-09 3:47

stancrm

31-Mar-09 3:47

Probably you called :

button.Click += new EventHandler(button_Click);

2 times...

Narendra Reddy Vajrala31-Mar-09 3:57

31-Mar-09 3:57

no..!
it was 1 time only

Ian Shlasko31-Mar-09 4:02

Ian Shlasko

31-Mar-09 4:02

You might want to run a Find in your solution for "BtnOk_Click", just to be certain of that. Remember, the designer will add one event hook and hide it in the InitializeComponent() method.

This may or may not be the problem, but it's best to eliminate the easy solutions first.

Narendra Reddy Vajrala31-Mar-09 4:12

31-Mar-09 4:12

hmmmmmmm
i did but it is showing single time only
Frown | :(

musefan31-Mar-09 3:54

31-Mar-09 3:54

Gonna have to see some code to help with this one

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

Narendra Reddy Vajrala31-Mar-09 3:57

31-Mar-09 3:57

private void BtnOk_Click(object sender, EventArgs e)
{
if (TxtTotMins.Text != TxtUCmins.Text)
return;

DateTime dt = Convert.ToDateTime(System.DateTime.Now.ToString());
DateTime Wo_dt = Convert.ToDateTime(System.DateTime.Now.ToShortDateString());
DateTime mod_time=Convert.ToDateTime(System.DateTime.Now.ToLongTimeString());
string QueueId = ClientInfo.Application + "!" + Wo_dt.ToShortDateString() + "!" + TransId;
string Upload = "N";

for (int i = 1; i <= OeCnt; i++)
{
string[] Level1 = OeControl[i].Level2.Tag.ToString().Split(':');
string Level1Code = Level1[1].ToString();
string Level2Code;
string Level3Code;

if (!(string.IsNullOrEmpty(OeControl[i].Level2.Text)))
{
string[] Level2 = OeControl[i].Level3.Tag.ToString().Split(':');
Level2Code = Level2[1].ToString();
}
else
Level2Code = null;

if (!(string.IsNullOrEmpty(OeControl[i].Level3.Text)))
{
string[] Level3 = OeControl[i].Level1.Tag.ToString().Split(':');
Level3Code = Level3[1].ToString();
}
else
Level3Code=null;

string Timespent=OeControl[i].TimeText.Text;

string Query = string.Format(@"insert into SIS_OEE(T_STAMP,oper,L2_Code,L3_Code,L4_Code,time_spent,
total_time,cono,cctr,emp,job,work_date,work_shift,mod_date,mod_time,
mod_user,sfis_trans_id,queue_id,upload) values ('{0}','{1}','{2}','{3}','{4}','{5}',
'{6}','{7}','{8}','{9}','{10}','{11}','{12}','{13}','{14}','{15}',{16},'{17}','{18}')", dt, TxtOperation.Text,
Level1Code, Level2Code, Level3Code, Timespent, TxtTotMins.Text, Cono, TxtCctr.Text,
Emp, TxtJob.Text, Wo_dt, Shift, Wo_dt, mod_time, Emp, TransId, QueueId, Upload);
Utility.SFISConnection.ExecuteNonQuery(Query);

}

this.Close();

}

this is mycode inside buttonclick

musefan31-Mar-09 4:02

31-Mar-09 4:02

well your query code if in a for loop so i can only assume that loop is running twice. Is this what you have indended?

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

Narendra Reddy Vajrala31-Mar-09 4:16

31-Mar-09 4:16

no no
for loop running fine but
it is coming again to
{ which is the first line under btn_click event
Frown | :(

musefan31-Mar-09 4:21

31-Mar-09 4:21

and then returns after the first if statement?

if you event is being called twice then it would suggest that you hav added it to the buttons Click event more than once, are there any other events attached to the button such as MouseClick, Enter etc.

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

Narendra Reddy Vajrala31-Mar-09 4:32

31-Mar-09 4:32

nowhere in my project btnOK_Click event twice, i checked in design page also.

musefan31-Mar-09 4:34

31-Mar-09 4:34

Ok, well Colin's suggestion below sounds good, give that a try

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Colin Angus Mackay31-Mar-09 4:30

Colin Angus Mackay

31-Mar-09 4:30

Narendra Reddy Vajrala wrote:
it is coming again to
{ which is the first line under btn_click event

So what is in the call stack? It will show you what called the method. Is the call stack different from the first time the method gets called? What called the method the second time around?

Narendra Reddy Vajrala31-Mar-09 4:40