DOCUMENT:Q193724 01-JUL-1999 [foxpro]
TITLE :PRB: Memory Leak Passing Arrays from VBScript to VFP
PRODUCT :Microsoft FoxPro
PROD/VER:WINDOWS:6.0
OPER/SYS:
KEYWORDS:kbGrpDSFox
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The information in this article applies to:
- Microsoft Visual FoxPro for Windows, version 6.0
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SYMPTOMS
========
When passing an array from VBScript code to a Visual FoxPro Component Object
Model (COM) Server, memory usage increases.
CAUSE
=====
For every STRING or UNITIALIZED array element, you lose one handle and 8 bytes
of memory.
RESOLUTION
==========
The following workaround initializes all elements of the array with numeric data
or Null before sending it to the COM Server.
<%@ LANGUAGE=VBScript ENABLESESSIONSTATE=False %>
This is a test
<%
dim myarray(30)
for i = 0 to 29
myarray(i) = 0 'Or Null
next
set ox = Server.CreateObject("arrayhandler.arrayhandler")
response.write ox.myeval("'
'+vers(1)+'
'+time()+" + _
"' '")
response.write ox.myeval("'
UserMem:'+sys(1016) + ''")
ox.DoNothingToArray myarray
set myarray(2) = NOTHING
set myarray(0) = NOTHING
set myarray(1) = NOTHING
set ox = NOTHING
set zzz = NOTHING
%>
STATUS
======
Microsoft is researching this problem and will post new information here in the
Microsoft Knowledge Base as it becomes available.
MORE INFORMATION
================
Steps to Reproduce Behavior
---------------------------
1. In a project named ArrayHandler, add the following code to the Main program:
DEFINE CLASS arrayhandler AS CUSTOM OLEPUBLIC
PROCEDURE DoNothingToArray
PARAM myarray
EXTERNAL ARRAY myarray
RETURN
ENDPROC
PROC mydocmd(p1)
&p1
PROC myeval(p1)
RETURN EVAL(p1)
ENDDEFINE
2. Build that project into a COM .dll file named ArrayHandler.dll.
3. Use the following code in an Active Server Page called ArrayTest.asp:
<%@ LANGUAGE=VBScript ENABLESESSIONSTATE=False %>
<%
dim myarray(30)
myarray(0) = "blah"
set ox = Server.CreateObject("arrayhandler.arrayhandler")
response.write ox.myeval("'
'+vers(1)+'
'+"+ _
"time() + ' '")
response.write ox.myeval("'
UserMem:'+sys(1016) + ''")
ox.DoNothingToArray myarray
set myarray(2) = NOTHING
set myarray(0) = NOTHING
set myarray(1) = NOTHING
set ox = NOTHING
set zzz = NOTHING
%>
4. Place the ArrayHandler.dll on a computer that has Internet Information Server
(IIS) and register the COM server.
5. Place the Active Server Page created in Step 3 in the InetPub\WWWRoot
directory on the IIS Server.
6. Run the .asp page by typing the following in the Address line of Internet
Explorer on the IIS Server and then press ENTER:
http://LOCALHOST/ARRAYTEST.ASP
When the page displays, press the F5 key to refresh. Notice the memory increase
with each refresh.
Additional query words: kbVFp600 kbCOMt kbISAPI kbInternet kbVBScript
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Keywords : kbGrpDSFox
Technology : kbVFPsearch kbAudDeveloper kbVFP600
Version : WINDOWS:6.0
Issue type : kbprb
Solution Type : kbpending
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Copyright Microsoft Corporation 1999.