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Q185859: INFO: OLE Servers Return Date Calculation Results as Seconds

Article: Q185859
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a 
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SUMMARY
=======

By default, a date data type passed in to or out of a Visual FoxPro OLE server
is automatically converted to Datetime format. Because of this, the result of a
date calculation is returned as seconds.

MORE INFORMATION
================

The Visual FoxPro OLE servers, by default, convert the Date data type to
DateTime. If you try to subtract two datetime() variables, within an OLE server,
the result is returned as seconds (n * 86400). You may use the TTOD() function
if you need the number returned as days.

Steps to Reproduce Behavior
---------------------------

1. Using Visual FoxPro, build an OLE DLL using the following code and name it
  DateFunc:

        DEFINE CLASS DateFunc AS custom OLEPUBLIC

           Name = "DateFunc"

           PROCEDURE DifferDate
              PARAMETERS BDate, EDate
              x=EDate-BDate
              RETURN INT(x)
          ENDPROC

        ENDDEFINE

2. After building the OLE DLL, issue the following commands in the Command
  window:

        ox=CREATEOBJECT("DateFunc.DateFunc")
        ? ox.Differdate({01/01/98},{01/05/98})

  Note that instead of returning four days, 345600 (4*86400) seconds is
  returned.

3. To return four days from the OLE DLL, replace the commands in the DifferDate
  procedure as shown below:

        PROCEDURE DifferDate
           PARAMETERS BDate, EDate
           x=ttod(EDate)-ttod(BDate)
           RETURN INT(x)
        ENDPROC

REFERENCES
==========

For additional information, please see the following articles in the Microsoft
Knowledge Base:

  Q168053 HOWTO: Visual FoxPro Automation Servers and Active Server Pages

  Q156014 How To Set Up OLE Automation in Visual FoxPro 5.0

Additional query words: kbDSupport kbdse VFP600REL kbole

======================================================================
Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP500a
Version           : WINDOWS:5.0,5.0a
Issue type        : kbinfo

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