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Why does this code for a worker thread not work?

Posted on 2008-09-29
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Last Modified: 2013-12-17
I have a windows form that writes a large text file to the hard disk, because of the size of the file the operation takes a long time and the user's work is disrupted.  I need to start a worker thread for this process to run in but I also would like to update the record count on the page regularly through the UI thread for a progress incicator.

I don't understand why the following code is not working.  I get a compilation error "The type or namespace name 'RecordDisplayEvents' could not be found (are you missing a using directive or an assembly reference?)" on line 330 and 332.
13 public partial class frmMain : Form
14     {
 ...
 
313        public void ShowRecCount(string msg, int recordsDone)
314        {
315            // ###########################################################
316            // Wrap the parameters in an EventArgs-derived custom class:
317            // ###########################################################
318
319            System.EventArgs e = new RecordDisplayEvents(msg, recordsDone);
320            object[] pList = { this, e };
321
322            // ###########################################################
323            // Invoke the method. This class is derived from Form,
324            // so we can just call BeginInvoke to get to the UI thread.
325            // ###########################################################
326
327            BeginInvoke(new RecordDisplayEventsHandler(UpdateUI), pList);
328        }
329
330        private delegate void RecordDisplayEventsHandler(object sender, RecordDisplayEvents e);
331
332        private void UpdateUI(object sender, RecordDisplayEvents e)
333        {
334            txtError.Text = e.Msg;
335            txtRecCount.Text = e.recordsDone.toString();
336        }
337    }

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Question by:mdcadu
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4 Comments
 

Expert Comment

by:naik_sanket
ID: 22596297
Did you try modifyung the access modifier of the delegate to public ? Or is it that you do not want to do that ?
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Accepted Solution

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Makolyte earned 250 total points
ID: 22596755
Where is the class "RecordDisplayEvents" defined?
0
 
LVL 37

Expert Comment

by:gregoryyoung
ID: 22598303
Makolyte has it right ... you actually have to define that class somewhere.
0
 

Author Closing Comment

by:mdcadu
ID: 31501177
This suggestion pointed me to where I was able to find the problem.
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