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PRE201: Introduction to Visual FoxPro

This Workshop introduces you to Visual FoxPro and thebasics o ho! to use it" Plan to attend this session i you#re

a be$innin$ Visual FoxPro de%eloper or you ha%en#t !orkedin Visual FoxPro beore& and you !ould like to $et 'ore out

o the (e%)on that ollo!s"

In the be$innin$& !as the dotWhat is Visual FoxPro?

Its a standalone tool for data manipulation

Its a development tool for standalone, LAN, client-server, !" and We#applications

Its a data#ase en$ine

Its a pro$rammin$ lan$ua$e

Its part of Visual %tudio

Its an inte$ral part of "icrosoft Windo&s

Its a reli$ion

Well, 'es and no( )he first four are pro#a#l' true( )he last three are pro#a#l' not,althou$h 'ou ma' find adherents &ho #elieve some, all, or none, of thosestatements( )he' also sa' theres one #orn ever' minute( Lets di$ a little, startin$&ith a little histor' lesson(

Wa'ne *atliff &as the pro$rammer, &or+in$ for "artin "arietta and su#contractin$for the et Propulsion La#orator', &ho started to create a natural-lan$ua$e-st'ledata#ase en$ine and manipulation lan$ua$e on his I"%AI .. computer, inassem#ler, in his spare time, in order to improve his chances in the foot#all pool( !nethin$ lead to another, and he &as soon mar+etin$ the product as d/A%0( It &aspurchased #' Ashton-)ate, then /orland, and is no& o&ned #' d/A%0, Inc( It &as onethe +e' products in the ma+in$ of the 1P *evolution2 of the 34.s that lead to a Pon ever' des+( In its he'da', a num#er of lan$ua$e-compati#le 1clones2 such asFox/ase, lipper, d#"AN and man' others competed fiercel' for the hearts andminds and &allets of developers(

Fox %oft&are, #ased in Perr's#ur$, !hio, &as formed and run #' 5r( 5avid Fulton(615r( 5ave2 as he &as affectionatel' +no&n, &as a $reat sho&man, &ho deli$hted in

meetin$ and presentin$ to his customers( 7e is a ma8or reason that 5evoncontinues to this da'(9 Fox %oft&are created a fast, interpreted version of the d/A%0runtime and then #ro+e the mold in $oin$ #e'ond the standard to introduce man'additional features( Fox/ase ran on "ac, 5!% and :nix platforms( FoxPro, startin$&ith version ;(

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apprentice, and 8ourne'man to reach the master level( Achievin$ master' is not asu#8ect that can #e tau$ht in a mornin$, nor covered in a short paper( /ut master'starts &ith a $ood understandin$ of the fundamentals, and that is &hat I tr' to coverhere( First, I loo+ at data, as is it the data that is reall' &hat it is all a#out @ theapplication is 8ust a &a' to #etter mana$e the data( %econd, I loo+ at the lan$ua$eitself, ho& to interact &ith the data, read it in and displa' it( )he third section $oes

#e'ond the #asic procedural parts of the lan$ua$e into the po&er tools, control ando#8ects that #uild applications( Finall', the fourth section tries to pull to$ether all ofthe previous sections, and provide a perspective and philosoph' of ho& an entireapplication should #e put to$ether(

Part I * It+s the (ata/efore &e can plun$e headfirst into developin$ FoxPro applications, a $lossar' and a#it of a#stract theor' &ill ma+e the applications &or+ much #etter(

Terminology

A fieldis a sin$le piece of information, such a persons first name or an items price(5ivide up 'our information so that fields can stand on their o&n, and dont need to #esu#-divided &hen 'ou are processin$( For example, if 'our part num#er is composedof a part t'pe, a re$ion code, a ratin$ and a su#-part num#er, such as AN->>-B-3;>B, it can often #e #etter to #rea+ that information into separate fields andcom#ine it &hen needed, rather than tr' to #e constantl' splittin$ the field &henloo+in$ for all parts from one re$ion(

0ach field has a sin$le datatype( 5ata t'pes hold a particular +ind of informationChave upper and lo&er limits on their capacit'C and are restricted on &hat informationthe' can hold( Fields ma' #e character, inte$er, date, datetime 6a com#ination ofdate and time9, numeric, dou#le, float, currenc' lo$ical 6true or false9, memo 6ver'lon$ freeform text or #inar' data9( %pecialiDed datat'pes exist to hold !L0information 6$eneral fields9, "acintosh #inar' 6picture fields9, #ut are rarel' used(

A collection of fields &hich hold a sin$le piece of information are $athered to$ether toform a record( For example, 'ou mi$ht record a chec+ received from a customer asE

Field name Type Data

ustomerNum#er

Inte$er B>;3

hec+ Num#er Inte$er

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3;B> >3;3 ;>; .3.334.3

>;>; B>;B>

>>B> .;.;;..;

;>;>; B; B>(>B .>.>34

.>

)his $eometr' leads to other names for the items, records are often called rowsandfields columns.

In FoxPro, there are usuall' three &a's to do an'thin$, or no &a' at all( )o create thista#le &e mi$ht t'peE

CREATE

And let the user interface $uide us to &hat &e &anted to create( !r &e could t'peE

CREATE TABLE CheckRec (Customer I, Check I, Amount N(9,2), Date D)

!rEDIMENSION a!"e#$%,&'#"mens"on a!"e#$%,&'a!"e#$,' *Customer*a!"e#$,2' *I*a!"e#$,+' %a!"e#$,%' a!"e#$,&' -!-a!"e#$2,' *CheckNo*a!"e#$2,2' *I*a!"e#$2,+' %a!"e#$2,%' a!"e#$2,&' -!-

a!"e#$+,' *Amount*a!"e#$+,2' *N*a!"e#$+,+' 9a!"e#$+,%' 2a!"e#$+,&' -!-a!"e#$%,' *ChkDate*a!"e#$%,2' *D*a!"e#$%,+' .a!"e#$%,%' a!"e#$%,&' -!-CREATE TABLE CheckRec !ROM ARRA/ a!"e#

0ach of these &a's of creatin$ a ta#le has advanta$es and disadvanta$es( )he first iseasiest for a #e$innerC he or she is $uided in the choices to #e made( )he second is

=uic+erC one line of t'pin$ and 'oure done( )he third form, thou$h, leads to the mostflexi#ilit' and control(

Design and Normalization

No& that 'ou have a #asic $rasp on ho& to create ta#les of data, 'ou face the tas+ ofdeterminin$ &hat $oes &here( %hould all of the data #e on one lar$e ta#le or shouldthe information #e sorted into several smaller ta#les?

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)he ans&er is nearl' al&a's the latter @ use multiple ta#les to separate differentitems( )here are exceptions, of course( If 'ou are creatin$ a =uic+ and dirt' set ofdata to use for a &ee+, and then thro& a&a', stuffin$ ever'thin$ into one ta#le &illma+e the processin$ @ 'our &or+ @ easier( /ut #e carefulJ I once created a set ofla#els to invite some customers to a $olf tournament( Five 'ears later, the out$ro&thof that s'stem &as chartin$ the financial course for a >...-person compan'(

)he rules for splittin$ up items #et&een ta#les are called normalization( 0ach ta#le6also called an entity9 contains all of the attri#utes 6fields9 for one item( If an entit'can have more than a =uantit' of one attri#ute 6for example, an order ma' have aseries of line items9, then those items $o into a second ta#le( )a#les are relatedtoone another #' a description of ho& information in one ta#le is associated &ithinformation in another( In the order example, the order num#er is stored in #othta#les, and &e can sa' that there is a one-to-manyrelationship #et&een the ta#lesEone order ma' have man' line items( )he t'pical relations areE

- one-to-man'E parent to man' children, such as an order to order item

- Dero-or-one-to man'E a loo+up ta#le ma' #e referenced in none, some orman' other records

- one-to-oneE data split across several ta#les for performance

)hese relationships defined in the desi$n sta$e &ill not #e of much use if the peopleusin$ the data#ase s'stem can add, su#tract or modif' data in all of the ta#les&ithout re$ard for the desi$n( For that reason, FoxPro provides relational integritytothe data#ase, throu$h the use of tri$$ers 6code automaticall' fired &hen a datachan$e ta+es place9 and stored procedures 6code stored &ithin the data#asecontainer9 to enforce the relationships defined on the data(

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"uch more information on data desi$n and normaliDation can #e found on theinternet or a $ood introductor' text on data#ase desi$n(

Reading and !riting data

Interactive

REPLACE, APPEND BLANK, BROWSE, EDIT

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VFP Commands

REPLACE, APPEND, COP, DELETE

S!L Commands

INSERT, "PDATE, DELETE

Transactions and buffering)here are some times in a relationship &hen 'ou are not read' to commit( )here aretimes &hen chan$es to a relational data#ase should not #e committed, either,perhaps #ecause a chan$e involves multiple ta#les and the chan$es are not 'etcomplete, or #ecause one of a set of chan$es failed to update properl'( 0nter#ufferin$ and transactions(

/ufferin$ allo&s data to #e stored on the local machine until all chan$es are read' to#e made at once( )his prevents t'in$ up shared data resources until the last possi#leminute, and allo&s local processin$ to examine old and ne& values of data 6eachstored in a separate #uffer9 to determine ho& a chan$e should #e handled(

)ransactions are the other end of the process, once 'ou are read' to commit the

data( A transaction loc+s data records as the chan$es are committed, and allo&s theentire set of updates 61a sin$le transaction29 to either #e completed successfull' orrolled #ac+ completel'( Visual FoxPro provides support #oth for local 65/F-#ased9transaction processin$ and for transaction processin$ in a client-server arran$ement(

Client server data

Why client*ser%er5

)here are three practical reasons to move a 5/F-#ased application to a client-serverarchitectureE

Too much dataE VFP has a ph'sical limit of ;K# for a sin$le ta#le or memo file, #ut

the limit can often #e hit earlier, &hen the amount of time to PA or *0IN50 a VFPta#le exceeds the recover' time of a client server s'stem follo&in$ a crash( As moreoperations move to&ards ;BxG, this factor has #ecome increasin$l' important(

High-security informationE While it is possi#le to crac+ a client-server data#ase,the li+elihood is far $reater in a VFP s'stem &here clients must have access to theunderl'in$ ta#les

Low bandwidthE VFP &as desi$ned to thrive in a net&or+ environment, and it ta+esadvant$e of the lar$e #and&idth to locall' cache file headers, indexes and records(While this results in remar+a#le *ushmore performance on a LAN, it can result inunaccepta#l' slo& performance in a WAN situation(

)here are numerous other, more pra$matic reasons to move to a client-serverarchitecture, includin$ the need for flexi#ilit' in distri#utin$ processin$, and the

political necessities of some environments(

The 4)I( test 6 4to'icity& )onsistency& Isolation& (urability

"an' or$aniDations 8ustif' their need for a client-server architecture &ith the AI5test( A &ell-desi$ned client server s'stem meets all of the follo&in$ criteriaE

Atomicit'E all data chan$es &ithin a transaction are treated as a sin$le indivisi#leunit, &here all are completed or all are rolled #ac+ as a unit(

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onsistenc'E the inte$rit' rules for the data#ase are enforced at all times, so that thedata#ase is al&a's in a consistent and valid state(

IsolationE results of a transaction are invisi#le until the' are complete, and onetransactions intermediate results should not affect another transaction( If onetransaction causes the initial conditions of a second transactions to fail, the secondtransaction should fail(

5ura#ilit'E once the data has #een committed, it &ill #e stored and retrieved even ifthe s'stem suffers the loss of a hard dis+ or a processor or an' other component thatdoesnt destro' the s'stem( )ransactions cannot #e 1lost(2

Part 6 It+s the codin$

"#$% commands& functions& ob'ect& $()s and design surfaces

/A%0 commandsE :%0, /*!W%0, *0PLA0, APP0N5, L!, 5!, IF, A%0

%ML commandsE %0L0), IN%0*), 50L0)0, :P5A)0

!utputE ? *0P!*) F!*", O%A, AL:LA)0, LI%)5I%PLA

)ext "anipulationE )extmer$e, LLFF, %trin$ functions

Controls

)ext-#ased controlsE La#el, )ext/ox, 0dit/ox, %pinner

Pic+-list controlsE om#o/ox, List/ox

/uttonsE ommand/uttons, !ption/uttonsKroups, hec+/oxes

ontainersC Krids, Pa$eFrames, ommand/uttonKroups

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Kraphical elementsE Ima$es, Lines, %hapes, %eparators 6tool#ars onl'9

!L0E #oth !L0/ound 6associated &ith data9 and ontainer 6!9 controls

Invisi#le controlE timer

*orking !ith controls

ontrols, in their simplest form, are simpl' the ne& versions of %As and K0)s( /utcontrols are so much moreJ )he' offer much finer control of the individual o#8ectsproperties, the a#ilit' to chan$e these properties at run-time, and the a#ilit' todefine the code &hich should run &hen an event happens( 0vents are also muchmore numerous, $ivin$ us the chance to create interfaces more responsive to theuser(

)he controls supplied &ith Visual FoxPro are the startin$ point( )hese controls can6and shouldJ9 #e su#classed to create our o&n custom controls( "ultiple controls ma'#e com#ined to form complex controls, #etter reflectin$ the complexit' and #usinessrules of the particular application( ustom controls can #e created, saved and reused(

$roperties

Properties descri#e a characteristic of a control( "ost are availa#le #oth at desi$nand run-time, one exception #ein$ the class properties, &hich are read-onl' &hen thecontrol is created( )hese properties are the data of the control &hich isencapsulated &ith the control( "ost controls share a num#er of commonpropertiesE

)o''on Property Purpose

)op, 7ei$ht, Left, Width )he location on the form ofthe o#8ect, if a visual control

omment Pro#a#l' the sin$le most

important propert'C letQs 'oufi$ure out &hat 'ou &eredoin$ &hen 'ou return to it

/aselass, lass,lassLi#rar'

)he pedi$ree of the control

Name 7o& the control is named #'all code &ithin the form&hich refers to it

Visi#le Whether the control shouldappear

5ra$"ode, 5ra$Icon /ehavior durin$ mouse dra$

operations

7elpontextI5 our hoo+ from the controlinto 'our custom help file

FontName, Font%iDe,FontItalic, Font/old,Font!utline,Font%tri+ethrou$h,Font:nderline

For all text-#ased controls

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olor%cheme, olor%ource,/orderolor, Foreolor,5isa#ledForeolor,/ac+olor,5isa#led/ac+olor

olors(

)hen, there are properties specific to an individual control or t&oE IntervalE ho& oftena )imer control fires,

%pinner7i$hValue, %pinnerLo&Value, and a sle& of othersJ

E%ents

0vents occur &hen the user has ta+en some action, or pro$rammaticall' &hen acontrol chan$es status( It is not possi#le to define ne& events( ommon eventsincludeE

E%ent PurposeInit ode run once &hen the

control is created

5estro' ode run &hen the control isreleased

5ra$5rop, 5ra$!ver 7o& to #ehave &hen adra$$ed o#8ect is over anddropped

"ouse"ove "ouse movement over acontrol

lic+, *i$htlic+, 5#llic+,

"ouse5o&n, "ouse:p

/oth mouse #uttonsJ

0rror 7o& errors are handled

KotFocus, LostFocus ode &hen control is ta##edto or clic+ed on

When, Valid !ur old friends(

7ethods

"ethods tend to #e more individual to the controls, as the' descri#e the uni=ue#ehavior of the control( )he most common areE

7ethod Purpose

5ra$ What to do if control isdra$$ed

"ove "oves controls &ithin acontainer

%etFocus Pro$rammaticall' sendfocus to a control

*efresh 0ach time the control needs

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to #e redispla'ed, the coderuns(

Individual methods include the *eset method for the )imer control, and the 5oVer#methods for the t&o !L0 controls(

7anipulatin$ controls: Property .heet 8 uilders

Propert' sheets, li+e our demo pro$ram, $ive us access to the various pro$ramma#leand fixed properties, events and methods( /uilders $ive an alternative vie& into alimited num#er of properties, simplif'in$ the construction of o#8ects(

Propert' sheets are tools that let us clim# under the hood and t&ea+ all the leversand dials( /uilders donQt have that depth, #ut donQt have the complexit', either(

A Typical Builder

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A Pro#ert$ S%eet

)reatin$ your o!n custo' controls

ou &ill &ant to create 'our o&n set of custom controls so that 'ou can manipulatethe #ase classes and modif' their properties and #ehaviors( It is a $ood idea to

create a set of Q$enericQ #ut su#classed controls and use these, rather than thestandard tool#ar, as the #asis for protot'pin$ screens( reate a custom control #'placin$ a control on a form, hi$hli$htin$ it, then selectin$ Q%ave as class((( from theFile menu(

"ost of the literature on the su#8ect of !!P states that it is a learnin$ process, and adifferent &a' of loo+in$ at pro#lems( Anticipate that 'our first solution ma' notal&a's #e the #est one( If possi#le, protot'pe 'our first development in Visual FoxProon a s'stem 'ou can thro& a&a'( In su#se=uent s'stems, #e&are of the pro#lem ofover-en$ineerin$ a solution(

5onQt #e afraid to thro& out 'our &or+(

5onQt su#class it to death - three or four levels is a#out all 'ouQll comprehend(

(vent model

In 'ears past, FoxPro &as #ased on a procedural model, &hen code started at the topof a procedure and executed line-#'-line until it &as done( "essa$e loops and 1Ket-less *0A5s2 could #e used to simulate an event-driven s'stem, #ut there &as a tric+'series of o#scure #ehaviors to $et it to &or+( With the advent of Visual FoxPro, a ne&,clean event model &as introduced that allo&s a much simpler and morecomprehensi#le approach to providin$ a trul' event-driven s'stem(

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What are E%ents5

An action, reco$niDed #' an o#8ect, for &hich 'ou can &rite code to respond( 0ventscan #e $enerated #' a user action, such as clic+in$ the mouse or pressin$ a +e', #'pro$ram code, or #' the s'stem, as &ith timers(

+ #o,$ro -elp #ile

E%ent irin$ se9uences

Pro#a#l' some of the most difficult functionalit' to understand( )'picall', a containercannot perform its action until its contents exist, therefore, o#8ects are created fromthe inside outE text#ox@Rcolumn@R$rid@Rpa$e@Rpa$eframe, and destro'ed in theopposite fashion, from the outside in, implodin$(

o! to pro$ra' or e%ents5

)he Foundation read is no more, except for le$ac' code &e attempt to mi$rate toVisual FoxPro( Forms are it( )he concept #ehind Visual FoxPro is that the initialapplication environment can #e set up, a menu can #e hoisted to the top of thescreen, and *0A5 0V0N)% &ill hold the entire application to$ether until the userchooses to =uit( )ime &ill tell if this model proves ro#ust enou$h for commercialapplications(

%o &hat are the ne& events?

E%ent 4pplies to: What it does ; !hat to put thereINI4 &ll ut Column7 eader7

*a5e7 Separator

Fires If it returns >F>7 o=ect is not

created> Contained o=ects fire efore

containers7 in t+e order added>

ERR.R Same Fires Fires efore .N ERR.R>

0ES4R.@ &o1e7 plusCommand2roup and

.ption2roup

Code runs =ust efore an o=ect is released>Containers fire efore contents>

0R&2.AER7

0R&20R.*

&o1e7 plus Cursor7

Custom7

0ataEn1ironment7

FormSet7 Relation7

4imer

Fires durin5 and upon completion respecti1ely

of a dra5 drop operation> Code must include

parameters statement to accept t+e dra55ed

o=ect reference and mouse coordinates>

$.9SE$.AE Column7 ut not to

ao1e7 plus .LEControl7

.LEBoundControl

4rac3s mouse mo1ements o1er an o=ect> &lso

passes status of Ctrl-&lt-S+ift 3eys7 as

CLICK7 $.9SE0.6N7

$.9SE9*

Not to Column7

ot+er

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9IEN&BLE C+ec3Bo,7 ComoBo,7

CommandButton7

Command2roup7

Container7 Control7

EditBo,7 2rid7 Ima5e7Lael7 Line7 ListBo,7

.LEBoundControl7.LEControl7

.ption2roup7

*a5eFrame7 S+ape7

Spinner7 4e,tBo,

Fires

RI24CLICK &o1e7 plus Form7

eader7 .ptionButton7

.ption2roup7 ut N.4

.LEBoundControl7

.LEControl

Ri5+t mouse clic3 on control>

2.4F.C9S7

L.S4F.C9S

C+ec3Bo,7 ComoBo,7

CommandButton7

Container7 Control7EditBo,7 Form7

ListBo,7

.LEBoundControl7

.LEControl7

.ptionButton7 Spinner7

4e,tBo,

.ccurs

A&LI07 6EN C+ec3Bo,7 ComoBo,7

CommandButton7

Command2roup7

EditBo,7 2rid7 ListBo,7

.ptionButton7

.ption2roup7 Spinner74e,tBo,

2ood old 6EN and A&LI07 fire efore

acceptin5 a c+an5e (after recei1in5 focus) and

after a c+an5e is made>

ERR.R$ESS&2E C+ec3Bo,7 ComoBo,7

CommandButton7Command2roup7

EditBo,7 ListBo,7

.ptionButton7

.ption2roup7 Spinner7

4e,tBo,

6+en A&LI0 returns a >F>7 allo Included for ac3 &not+er ac3 *roperty StatusBar4e,t pro1ides

similar capailities>

KE@*RESS C+ec3Bo,7 ComoBo,7

CommandButton7

EditBo,7 Form7 ListBo,7

.ptionButton7 Spinner7

4e,tBo,

&llo

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Interacti1eC+an5e7

*ro5rammaticC+an5e

C+ec3Bo,7 ComoBo,7 7

Command2roup7

EditBo,7 ListBo,7

.ption2roup7 Spinner7

4e,tBo,

6+at 9*0&4E0() al Fires eac+ time a c+an5e is

made 1ia mouse or 3eyoard7 e1en efore focus

+as s+ifted from t+e control> IN4ER&C4IAE

detects user c+an5es7 *R.2R&$$&4ICc+an5es performed in code>

&C4IA&4E70E&C4IA&4E Form7 FormSet7 *a5e74oolar Similar to t+e #>, Screens s+o< clause> .ccurside() also runs 0E&C4IA&4E

R&N2EI27

R&N2EL.6

ComoBo,7 Listo,7

Spinner7 4e,tBo,

0ual functions> For ComoBo, and ListBo,7

returns t+e initially selected element For Spinners

4e,tBo,es acts as a R&N2E test7 returnin5 a

numeric

0.6NCLICK ComoBo,7 ListBo,7

Spinner

Not to e confused C&94I.N: dontRESIE or refres+() o=ects .ccurs efore .pen4ales()

met+od and after Close4ales() met+ods>

&F4ER0.CK7

BEF.RE0.CK7

9N0.CK7

4oolar Code

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need arises( Anticipate some $reat third part' tools that +no& ho& to reall' ta+eadvanta$e of all the ne& features(

The tools

Pro8ect "ana$ers

ode 0ditor

Form 5esi$ner

lass 5esi$ner

"enu 5esi$ner

Part III: 4d%anced topics!#8ect oriented anal'sis and desi$n

!" and n-tier desi$n

:ser Interface 5esi$n

Pro8ect "ana$ement

Part IV: Puttin$ it all to$ether*)F" @ VFP comes &ith an excellent set of resources( /ro&se the help file( )here is atremendous amount of &ell-or$aniDed material there(

5ont fi$ht the tide( Learn to #ecome one &ith the Fox #' thin+in$ the &a' the Foxthin+s(

Ket a frame&or+

Ket a support $roupE mailin$ lists, online communities, ma$aDines T ne&sletters

%harpen the sa& @ #oo+s and conferences

)op )en "ista+es

.bout the .uthor

Ted Roche

Ted Roche

Associates! LL"

)ed *oche is president of)ed *oche T Associates, LL, aconsultin$ firm #ased in Ne& 7ampshire( 7e is author ofEssential SourceSafe, co-author &ith )amar Kranor of thea&ard-&innin$ Hacker's Guide to Visual FoxPro 6, and acontri#utor to < other FoxPro #oo+s( A former ontri#utin$0ditor for FoxPro Advisor ma$aDine, )ed is a "icrosoftertified %olution 5eveloper, %'stems 0n$ineer and seven-time "icrosoft %upport "ost Valua#le Professional( ontact

)ed at tedrochetedroche(com

References

"' 3

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least, lur+ in the #ac+$round for a &hile( )he support and education is invalua#le, ata ver' reasona#le cost(

/nline co''unities

Nearl' the $randdadd' of them all, ompu%erve has opened their forums to the &e#(%tart at httpE&&&(compuserve(com, and $o from there( A direct lin+ that &or+s forme is httpE$o(compuserve(com"%5evApps?locUus- 'our milea$e ma' var'(

Pro#a#l' the most active FoxPro communit' on the &e# toda' ishttpE&&&(universalthread(com, &ith man' &ell-+no&n authors and spea+ersfre=uentin$ the site( A close runner-up is the repositor' of +no&led$e #uilt up #' itsmem#ers at httpEfox(&i+is(com- a remar+a#le, or$anic site that allo&s visitors toadd, edit and enhance the existin$ &e# site( /ut there are a num#er of other&orth&hile sites( *od Paddoc+ hosts httpE&&&(foxforum(com( 0d Leafe hosts theProFox mailin$ listC 'ou can si$n up at httpE&&&(leafe(com, and the Virtual FoxPro:ser Kroup is online at httpE&&&(vfu$(or$(

ooks

Im a #i$ advocate of learnin$ #' readin$( )here are a lot of fascinatin$ #oo+s outthere, and I am al&a's in the process of readin$ a fe& at a time( If this isnt 'ourst'le, consider han$in$ around &ith people &ho are +eepin$ up &ith the latest #oo+s@ #' visitin$ their &e# sites, listenin$ to them at conferences and user $roupmeetin$s, or &or+in$ &ith them(

%teven /lac+ has an extensive readin$ list at httpE&&&(steven#lac+(com- loo+ for1#oo+shelf(2 Whil 7entDen maintains another list at httpE&&&(hentDen&er+e(com-his is called 1)he %tac+s(2 /et&een those t&o lists alone, 'ou &ill find most, if not all,of the #oo+s I &ould recommend as &ell(

7a$a

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,inks

&n e,cellent e,planation of t+e &CI0 principles is a1ailale on

!ttp:""###$asdigita$com"books"panda"databases%c!oosing

Lammers, %usan, Programmers at Work"icrosoft Press, 34, features a fascinatin$intervie& &ith Wa'ne *atliff 6&hile he had an office at Ashton-)ate, and the I/" A)&as considered a #ar$ain at H,...9

dBASEis a re&istered trademar' o( dBASE Inc) Ot%er dBASE Inc) #rod*ct names are trademar'sor re&istered trademar's o( dBASE Inc)

!ri$inall' presented as a pre-conference session at the FoxPro 5ev ;..3, %an 5ie$o,A, %eptem#er , ;..3( op'ri$ht +;..3-;.. #' )ed *oche(

)his &or+ is licensed under the reative ommons Attri#ution-Noncommercial-%hareAli+e >(. :nited %tates License( )o vie& a cop' of this license, visithttpEcreativecommons(or$licenses#'-nc-sa>(.us or send a letter to reativeommons, 3G3 %econd %treet, %uite >.., %an Francisco, alifornia, 4B3.