Executing Long-Running Tasks with the Progress Bar in ASP.NET - Showing the progress

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This is the actual section which shows the progress to the user in the form of a progress bar.  The “UnderProcess.vb” takes care of this process. 

The “UnderProcess.vb” mainly contains two labels, “lblMsg” and “lblProgressBar.”  “lblMsg” shows what percentage it has completed in the form of words.  “lblProgressBar” was designed with a blue background color.  This gets expanded (indirectly; the width of the label) based on the percentage value for every auto-refresh of the same page.  The following is the entire code present in the “page load“ event of “UnderProcess.vb.”

' Get the request id
Dim requestId As New Guid(Request.
QueryString("RequestId").ToString())
'Check the processing thread status collection
If (ProcessingStatus.Contains(requestId))Then
  'StatusValue contains either a value between 0 to 100 or -1 (-1 shows that the task is finished)
  Dim StatusValue As Integer =
CType(ProcessingStatus.getValue(requestId), Integer)
  If StatusValue = -1 Then
  'processing task succesfully finished
    ProcessingStatus.remove(requestId)
    'remove the status
    Response.Redirect("finshed.aspx")
    'go to result page
  EndIf

  'if not finished, display the status
  ' Remove the status from the collection
  Me.lblMsg.Text = "Wait for a moment.." & StatusValue & "% Completed.."
  Me.lblProgressBar.Width = Unit.Pixel(2 * StatusValue)
  '200 pixels for 100%
EndIf

' The processing  has not yet finished
' Add a refresh header, to refresh the page in 2 seconds.
Response.AddHeader("Refresh", "2")

I commented the above program very clearly to help you understand every statement in detail. I hope you can understand it.

The “Finshed.aspx” has nothing other than a simple label with a message “Completed Successfully.”  No processing is done at “Finished.aspx”.

Next: What is “ProcessingStatus.vb” in detail? >>
 

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Comments On: Executing Long-Running Tasks with the Progress Bar in ASP.NET

· Thanx a lot for this. I've always thought that multithreading is only useful for...    · Hello,The article is just only to give you an idea of implementing the progress...    · You can still further discuss, if you have doubts. I am here to answer you.    · Any thoughts on how this might be applied to file uploads? It seems like the...    · You might use the concept of "streaming the binary content" for your requirement. I...    · Hi, Thanks for sharing this code. My question is how is the 'requestId' got removed...    · Good catch! Even I never thought of it. Right now, I could not think of very good...    · I copied and run the code in my machine and getting "ProcessingStatus not defined"...    · Have you had any further thoughts on "how is the 'requestId' got removed in case...    · Hi thereI'm trying to use your example but the doprocess is not starting and...    · Hi,I'm also using your technique to show progress, however i'm concerned about...   >>> Post your comment now!