FIX: GetChunk Freezes Unless Other Events Happening

• Microsoft Visual Basic Enterprise Edition for Windows, version 5.0
  on the following platforms: Alpha

SYMPTOMS

The GetChunk operation pauses unless other events are happening. Other events could include moving the mouse, which would trigger the GetChunk to continue.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This bug has been fixed in Visual Studio 97 Service Pack 2.

For more information on the Visual Studio Service Pack 2, please see the following article in the Microsoft Knowledge Base:

Q170365 : INFO: Visual Studio 97 Service Packs - What, Where, and Why

Q171554 : INFO: Visual Basic 5.0 Fixes in Visual Studio 97 Service Pack 2

MORE INFORMATION

Steps to Reproduce Behavior

1. Run Visual Basic or, if Visual Basic is already running, choose New Project from the File menu (ALT, F, N). Form1 is created by default. Add the following code to the General Declarations of Form1:

   
         Option Explicit
         Private bwait As Boolean
    




2. Place an Internet Transfer Control (Inet1) on Form1, and add the following code:

   
         Private Sub Inet1_StateChanged(ByVal State As Integer)
           Dim s$, t$
           Debug.Print "StateChanged:", State
           If State = icResponseCompleted Then
              t$ = ""
              s$ = Inet1.GetChunk(1024)
              DoEvents
              While Len(s$) <> 0
                  t$ = t$ & s$
                  s$ = Inet1.GetChunk(1024)
                  DoEvents: DoEvents: DoEvents
                  Debug.Print ".";
              Wend
              Debug.Print
              Debug.Print Left$(t$, 20), Len(t$)
              bwait = True
           End If
         End Sub
    




3. Place a CommandButton (Command1) on Form1, and add the following code:

   
         Private Sub Command1_Click()
            Dim i As Integer
            Dim tmp As Single
   
            For i = 1 To 5
             tmp = Timer
             While tmp + 1 > Timer
                  DoEvents: DoEvents: DoEvents
             Wend
             bwait = False
             Inet1.Execute "http://msw"
             While Not (bwait)
              DoEvents
             Wend
            Next
         End Sub
    




4. Press the F5 key to run it, and then press the ENTER key to invoke the command_click. (NOTE: Do not move the mouse or touch the keyboard.)



5. Watch your debug window. The first time you access the page, it works. However, the second time, you need to pause. Press Ctrl-break quickly and you are at the Doevents statement following the GetChunk. If you move the mouse, the GetChunk will continue.

Additional query words:

Keywords : kbVBp500 kbVS97sp2fix kbvbp500sp2fix
Version : WINDOWS:5.0
Platform : NT WINDOWS
Issue type : kbbug