The LA Fox Developer Newsletter

December 2000

Command Manager

by Jeff Bowman

Here’s a handy little utility you can use when you get tired of

typing all of those lengthy ‘MODIFY CLASS’ and ‘DO FORM’

commands in your Command Window.

The idea was borne of frustration with either manually typing

out cumbersome commands, plus path and filename, or of

maintaining an awkward ON KEY LABEL list. The list

approach is certainly easier than typing the commands, or even

navigating the Open File dialog, but you still have to maintain a

program file. In order to change an OKL, you must laboriously

copy-and-paste the command text (after wrangling the path and

filename in the first place), and rerun the program each time

you want to update the list. You’ll also probably keep running

out of available OKLs that make sense and are consistent with

what you’re working on at the time.

Command Manager solves all that. Assign an OKL in your

startup program to run the form (e.g., ‘ON KEY LABEL F5 DO

FORM c:\tools\manager’), and you’ve now extended that one

OKL to up to twenty MODIFY and/or RUN commands.

To use Command Manager, first load the filename you want to

process into one of the fields on the form. You do this by

clicking the ellipsis button to the right of the desired field.

Navigate to the file of interest and click Select (if you’ve chosen

a class library, you’ll be prompted to select a class from that

library). You can now process the command by tapping the

desired number on your keyboard, and then either ‘M’ or ‘R’ to

modify or run the specified file. You’ll notice that certain file

types, when selected, disable the ‘Run’ functionality; this is

because that file type cannot be run from the VFP Command

Window. All file types, of course, may be modified.

I hope you find Command Manager to be of use to you. I

finished it only recently, and therefore have used it only a few

times, but even those few times have been enough to make me

glad I have it. Some planned features are the ability to pass

parameters with a ‘Run’ command, pasting of the executed

command into the VFP Command Window, and allowing

execution of other VFP code before processing a command.

You may download Command Manager or any of several Visual

FoxPro-related utilities and code samples from

http://www.jeffbowman.com/. Send any comments or bug

reports to jbowman©jeffbowman.com, and if you would like to

be added to a mailing list to stay informed of updates on any

code that you download from the site, send an email to that

effect, specifying your interest.

Happy coding!

(Con’t, page 9)

Detecting DCOM Installation

Under VFP6

VFP6 needs DCOM to be properly installed if you disable the

VFP main windows through CON FIG.FPW; at termination, VFP

will cause a C0000005 error. There are other situations involving

ON SHUTDOWN which may show some of the same symp-

toms if DCOM isn’t there.

DCOM can get put on a system in several ways; under WinNT.

installation of SP3 or SP4 should add DCOM support, as would

installation of 1E4. Win98 should always have DCOM support

loaded unless by some quirk of fate 1E4 misinistalled. Win95

systems can add DCOM by installing lE4, or by installing the

support either from the DCOM95 version 1.2 support file (a self-

extracting .EXE) or the DCOM98.EXE found on the Visual

Studio distribution.

The C0000005 error only occurs if SCREEN=OFF and you

subsequently make either the VFP main screen visible

(_screen.visible = .t.) or activate a top-level form. You can detect

that DCOM is missing and shut down before anything happens

using the Registry class in the FFC and MESSAGEBOXO to

display a message without making a form visible:

#INCLUDE REGISTRY.H

#DEFINE DCOMKEYSTRING 'SOFTWARE\Microsoft\OLE'

*

note the preceding line was corrected to remove the leading “V

#DEFINE ENABLEDCOMKEY ‘EnabIeDCOM’

SET CLASSLIB TO REGIsTRY.vcx

oReg=cREATEOBJ(’registry’)

LOCAL IFoundDCOM

IFoundDCOM = .F.

IF

oReg.OpenKey(DcOMKEYSTRING,HKEY_LOcAL_MAcHINE,.F.) = 0

LOCAL cValue

cValue

IF

oReg.GetKeyValue(ENABLEDCOMKEY,~cVaIue) =0

IFoundDcOM =! EMPTY(cValue)

ENDIF

ENDIF

IF

I IFoundDCOM

MESSAGEBOX(’DCOM not present on system. Please install it

before running this application’,

16,;

‘Missing Windows Component’)

QUIT

ENDIF

Don’t forget...

DevConnections 2001

http://www.devconnections.com

Page 8