OReilly learning PHP 5 jun 2004 ISBN 0596005601

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TableofContents
Index
Reviews
ReaderReviews
Errata
Academic

LearningPHP5
ByDavidSklar

Publisher :O'Reilly
PubDate :June2004
ISBN :0-596-00560-1
Pages :368


LearningPHP5istheidealtutorialforgraphic
designers,bloggers,andotherwebcrafters
whowantathoroughbutnon-intimidating
waytounderstandthecodethatmakesweb
sitesdynamic.Thebookbeginswithan
introductiontoPHP,thenmovestomore

advancedfeatures:languagebasics,arrays
andfunctions,webforms,connectingto
databases,andmuchmore.Completewith


exercisestomakesurethelessonsstick,this
bookofferstheidealclassroomlearning
experiencewhetheryou'reinaclassroomor
onyourown.



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•
•
•
•
•


TableofContents
Index
Reviews
ReaderReviews
Errata
Academic

LearningPHP5
ByDavidSklar

Publisher :O'Reilly
PubDate :June2004
ISBN :0-596-00560-1
Pages :368



Copyright

Dedication

Preface
WhoThisBookIsFor

ContentsofThisBook




OtherResources




UsingCodeExamples

ConventionsUsedinThisBook
CommentsandQuestions

Acknowledgments

Chapter1.OrientationandFirstSteps
Section1.1.PHP'sPlaceintheWebWorld




Section1.2.What'sSoGreatAboutPHP?
Section1.3.PHPinAction
Section1.4.BasicRulesofPHPPrograms



Section1.5.ChapterSummary


Chapter2.WorkingwithTextandNumbers
Section2.1.Text




Section2.2.Numbers




Section2.4.ChapterSummary

Section2.3.Variables
Section2.5.Exercises


Chapter3.MakingDecisionsandRepeatingYourself
Section3.1.Understandingtrueandfalse

Section3.2.MakingDecisions




Section3.3.BuildingComplicatedDecisions




Section3.5.ChapterSummary

Section3.4.RepeatingYourself
Section3.6.Exercises


Chapter4.WorkingwithArrays
Section4.1.ArrayBasics

Section4.2.LoopingThroughArrays

Section4.3.ModifyingArrays




Section4.5.UsingMultidimensionalArrays

Section4.4.SortingArrays
Section4.6.ChapterSummary

Section4.7.Exercises


Chapter5.Functions
Section5.1.DeclaringandCallingFunctions




Section5.2.PassingArgumentstoFunctions




Section5.4.UnderstandingVariableScope

Section5.3.ReturningValuesfromFunctions
Section5.5.ChapterSummary

Section5.6.Exercises


Chapter6.MakingWebForms
Section6.1.UsefulServerVariables




Section6.2.AccessingFormParameters




Section6.4.ValidatingData




Section6.6.PuttingItAllTogether



Section6.8.Exercises

Section6.3.FormProcessingwithFunctions
Section6.5.DisplayingDefaultValues
Section6.7.ChapterSummary

Chapter7.StoringInformationwithDatabases



Section7.1.OrganizingDatainaDatabase




Section7.2.ConnectingtoaDatabaseProgram




Section7.4.PuttingDataintotheDatabase




Section7.6.GeneratingUniqueIDs




Section7.8.RetrievingDatafromtheDatabase

Section7.10.RetrievingFormDataSafely




Section7.12.MySQLWithoutPEARDB

Section7.3.CreatingaTable
Section7.5.InsertingFormDataSafely
Section7.7.ACompleteDataInsertionForm
Section7.9.ChangingtheFormatofRetrievedRows
Section7.11.ACompleteDataRetrievalForm
Section7.13.ChapterSummary

Section7.14.Exercises


Chapter8.RememberingUserswithCookiesandSessions
Section8.1.WorkingwithCookies




Section8.2.ActivatingSessions




Section8.4.ConfiguringSessions

Section8.6.Whysetcookie()andsession_start()WanttoBeattheTopofthe
Page
Section8.7.ChapterSummary




Section8.3.StoringandRetrievingInformation
Section8.5.LoginandUserIdentification

Section8.8.Exercises


Chapter9.HandlingDatesandTimes
Section9.1.DisplayingtheDateorTime

Section9.2.ParsingaDateorTime




Section9.3.DatesandTimesinForms




Section9.5.ChapterSummary

Section9.4.DisplayingaCalendar
Section9.6.Exercises


Chapter10.WorkingwithFiles
Section10.1.UnderstandingFilePermissions

Section10.2.ReadingandWritingEntireFiles




Section10.3.ReadingandWritingPartsofFiles




Section10.5.InspectingFilePermissions

Section10.4.WorkingwithCSVFiles
Section10.6.CheckingforErrors




Section10.7.SanitizingExternallySuppliedFilenames

Section10.8.ChapterSummary
Section10.9.Exercises


Chapter11.ParsingandGeneratingXML
Section11.1.ParsinganXMLDocument

Section11.2.GeneratinganXMLDocument




Section11.3.ChapterSummary
Section11.4.Exercises


Chapter12.Debugging
Section12.1.ControllingWhereErrorsAppear

Section12.2.FixingParseErrors




Section12.3.InspectingProgramData

Section12.5.ChapterSummary

Section12.4.FixingDatabaseErrors
Section12.6.Exercises


Chapter13.WhatElseCanYouDowithPHP?
Section13.1.Graphics

Section13.2.PDF




Section13.3.Shockwave/Flash




Section13.5.SendingandReceivingMail




Section13.7.TheHTML_QuickFormForm-HandlingFramework




Section13.9.AdvancedXMLProcessing

Section13.11.RunningShellCommands




Section13.13.Encryption




Section13.15.IMAP,POP3,andNNTP




Section13.17.PHP-GTK

Section13.4.Browser-SpecificCode
Section13.6.UploadingFilesinForms
Section13.8.ClassesandObjects
Section13.10.SQLite
Section13.12.AdvancedMath
Section13.14.TalkingtoOtherLanguages
Section13.16.Command-LinePHP
Section13.18.EvenMoreThingsYouCanDowithPHP

AppendixA.InstallingandConfiguringthePHPInterpreter
SectionA.1.UsingPHPwithaWeb-HostingProvider

SectionA.2.InstallingthePHPInterpreter



SectionA.3.InstallingPEAR




SectionA.4.DownloadingandInstallingPHP'sFriends




SectionA.5.ModifyingPHPConfigurationDirectives
SectionA.6.AppendixSummary


AppendixB.RegularExpressionBasics
SectionB.1.CharactersandMetacharacters




SectionB.2.Quantifiers

SectionB.4.CharacterClasses




SectionB.6.PHP'sPCREFunctions

SectionB.3.Anchors
SectionB.5.Greed
SectionB.7.AppendixSummary

SectionB.8.Exercises


AppendixC.AnswersToExercises
SectionC.1.Chapter2




SectionC.2.Chapter3




SectionC.4.Chapter5

SectionC.6.Chapter7




SectionC.8.Chapter9




SectionC.10.Chapter11

SectionC.3.Chapter4
SectionC.5.Chapter6
SectionC.7.Chapter8
SectionC.9.Chapter10
SectionC.11.Chapter12

SectionC.12.AppendixB


Colophon

Index


Copyright©2004O'ReillyMedia,Inc.

PrintedintheUnitedStatesofAmerica.
PublishedbyO'ReillyMedia,Inc.,1005GravensteinHighway
North,Sebastopol,CA95472.
O'Reillybooksmaybepurchasedforeducational,business,or
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contactourcorporate/institutionalsalesdepartment:(800)
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NutshellHandbook,theNutshellHandbooklogo,andthe
O'ReillylogoareregisteredtrademarksofO'ReillyMedia,Inc.
LearningPHP5,theimageofaneagle,andrelatedtradedress
aretrademarksofO'ReillyMedia,Inc.
Manyofthedesignationsusedbymanufacturersandsellersto
distinguishtheirproductsareclaimedastrademarks.Where
thosedesignationsappearinthisbook,andO'ReillyMedia,Inc.
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Whileeveryprecautionhasbeentakeninthepreparationofthis
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errorsoromissions,orfordamagesresultingfromtheuseof
theinformationcontainedherein.


Dedication
ToJacob,whocanlookforwardtosomuchlearning.


Preface
Boringwebsitesarestatic.Interestingwebsitesaredynamic.
Thatis,theircontentchanges.AgiantstaticHTMLpagelisting

thenames,pictures,descriptions,andpricesofall1,000
productsacompanyhasforsaleishardtouseandtakes
forevertoload.Adynamicwebproductcatalogthatletsyou
searchandfilterthoseproductssoyouseeonlythesixitems
thatmeetyourpriceandcategorycriteriaismoreuseful,faster,
andmuchmorelikelytocloseasale.
ThePHPprogramminglanguagemakesiteasytobuilddynamic
websites.Whateverinteractiveexcitementyouwantto
createsuchasaproductcatalog,ablog,aphotoalbum,oran
eventcalendarPHPisuptothetask.Andafterreadingthis
book,you'llbeuptothetaskofbuildingthatdynamicwebsite,
too.


WhoThisBookIsFor
Thisbookisfor:
Ahobbyistwhowantstocreateaninteractivewebsitefor
himself,hisfamily,oranonprofitorganization.
AwebsitebuilderwhowantstousethePHPsetupprovided
byanISPorhostingprovider.
Asmallbusinessownerwhowantstoputhercompanyon
theWeb.
Apagedesignerwhowantstocommunicatebetterwithher
developerco-workers.
AJavaScriptwhizwhowantstobuildserver-sideprograms
thatcomplementherclient-sidecode.
AbloggerorHTMLjockeywhowantstoeasilyadddynamic
featurestohersite.
APerl,ASP,orColdFusionprogrammerwhowantstogetup
tospeedwithPHP.

Anybodywhowantsastraightforward,jargon-free
introductiontooneofthemostpopularprogramming
languagesforbuildinganinteractivewebsite.
PHP'sgentlelearningcurveandapproachablesyntaxmakeitan
ideal"gateway"languageforthenontechnicalwebprofessional.
LearningPHP5isaimedatboththisinterested,intelligent,but
notnecessarilytechnicalindividualaswellasatprogrammers


familiarwithanotherlanguagewhowanttolearnPHP.
Asidefrombasiccomputerliteracy(knowinghowtotype,
movingfilesaround,surfingtheWeb),theonlyassumptionthat
thisbookmakesaboutyouisthatyou'reacquaintedwithHTML.
Youdon'tneedtobeanHTMLmaster,butyoushouldbe
comfortablewiththeHTMLtagsthatpopulateabasicwebpage
suchas<html>,<head>,<body>,

,<a>,and
.Ifyou're
notfamiliarwithHTML,readHTML&XHTML:TheDefinitive
Guide,FifthEdition,byBillKennedyandChuckMusciano
(O'Reilly).


ContentsofThisBook
Thisbookisdesignedsothatyoustartatthebeginningand
workthroughthechaptersinorder.Forthemostpart,each
chapterdependsonmaterialinthepreviouschapters.Chapter
2,throughChapter12andAppendixB,eachendwithexercises
thattestyourunderstandingofthecontentinthechapter.
Chapter1,providessomegeneralbackgroundonPHPandhow
itinteractswithyourwebbrowserandawebserver.Italso
showssomePHPprogramsandwhattheydotogiveyouan

ideaofwhatPHPprogramslooklike.Especiallyifyou'renewto
programmingorbuildingdynamicwebsites,itisimportantto
readChapter1.
Thenextfourchaptersgiveyouagroundinginthe
fundamentalsofPHP.Beforeyoucanwritegreatliterature,you
needtolearnalittlegrammarandsomevocabulary.That's
whatthesechaptersarefor.(Don'tworryyou'lllearnenough
PHPgrammarandvocabularyrightawaytostartwritingsome
shortprograms,ifnotgreatliterature.)Chapter2showsyou
howtoworkwithdifferentkindsofdatasuchaspiecesoftext
andnumbers.Thisisimportantbecausethewebpagesthat
yourPHPprogramsgeneratearejustbigpiecesoftext.Chapter
3,describesthePHPcommandswithwhichyourprogramscan
makedecisions.Thesedecisionsareattheheartofthe
"dynamic"in"dynamicwebsite."TheconceptsinChapter3are
whatyouuse,forexample,todisplayonlyitemsinaproduct
catalogthatfallbetweentwopricesauserentersinaweb
form.
Chapter4,introducesarrays,whicharecollectionsofabunch
ofindividualnumbersorpiecesoftext.Manyfrequentactivities
inPHPprograms,suchasprocessingsubmittedwebform
parametersorexamininginformationpulledoutofadatabase,
involveusingarrays.Asyouwritemorecomplicatedprograms,


you'llfindyourselfwantingtorepeatsimilartasks.Functions,
discussedinChapter5,helpyoureusepiecesofyourprograms.
Thethreechaptersafterthatcoverthreeessentialtasksin
buildingadynamicwebsite:dealingwithforms,databases,and
users.Chapter6,suppliesthedetailsonworkingwithweb

forms.Thesearetheprimarywaythatusersinteractwithyour
website.Chapter7,discussesdatabases.Adatabaseholdsthe
informationthatyourwebsitedisplays,suchasaproduct
catalogoreventcalendar.Thischaptershowsyouhowtomake
yourPHPprogramstalktoadatabase.Withthetechniquesin
Chapter8,yourwebsitecandouser-specificthingssuchas
displaysensitiveinformationtoauthorizedpeopleonlyortell
someonehowmanynewmessageboardpostshavebeen
createdsinceshelastloggedin.
Then,thenextthreechaptersexaminethreeotherareasyou're
likelytoencounterwhenbuildingyourwebsite.Chapter9,
highlightsthestepsyouneedtotake,forexample,todisplaya
monthlycalendarortoallowuserstoinputadateortimefrom
awebform.Chapter10,describesthePHPcommandsfor
interactingwithfilesonyourowncomputerorelsewhereonthe
Internet.Chapter11,suppliesthebasicsfordealingwithXML
documentsinyourPHPprograms,whetheryouneedto
generateoneforanotherprogramtoconsumeoryou'vebeen
providedwithonetouseinyourownprogram.
Chapter12andChapter13eachstandontheirown.Chapter
12,furnishessomeapproachesforunderstandingtheerror
messagesthatthePHPinterpretergeneratesandhuntingdown
problemsinyourprograms.Whileitpartiallydependsonearlier
material,itmaybeworthwhiletoskipaheadandperuse
Chapter12asyou'reworkingthroughthebook.
Chapter13servesatasteofmanyadditionalcapabilitiesofPHP,
suchasgeneratingimages,runningcodewritteninother
languages,andmakingFlashmovies.Afteryou'vegotten
comfortablewiththecorePHPconceptsexplainedinChapter1

throughChapter12,visitChapter13forlotsofnewthingsto
learn.
Thethreeappendixesprovidesupplementarymaterial.Torun
PHPprograms,youneedtohaveacopyofthePHPinterpreter
installedonyourcomputer(orhaveanaccountwithawebhostingproviderthatsupportsPHP).AppendixA,helpsyouget
upandrunning,whetheryouareusingWindows,OSX,or
Linux.
Manytext-processingtasksinPHP,suchasvalidatingsubmitted
formparametersorparsinganHTMLdocument,aremade
easierbyusingregularexpressions,apowerfulbutinitially
inscrutablepatternmatchingsyntax.AppendixB,explainsthe
basicsofregularexpressionssothatyoucanusetheminyour
programsifyouchoose.
Last,AppendixC,containstheanswerstoalltheexercisesin
thebook.Nopeekinguntilyoutrytheexercises!


OtherResources
TheonlineannotatedPHPManual( />isagreatresourceforexploringPHP'sextensivefunction
library.Plentyofuser-contributedcommentsofferhelpfuladvice
andsamplecode,too.Additionally,therearemanyPHPmailing
listscoveringinstallation,programming,extendingPHP,and
variousothertopics.Youcanlearnaboutandsubscribetothese
mailinglistsatAreadonlywebinterfacetothemailinglistsisat.
AlsoworthexploringisthePHPPresentationSystemarchiveat
.Thisisacollectionofpresentationsabout
PHPthathavebeendeliveredatvariousconferences.
Afteryou'recomfortablewiththematerialinthisbook,the
followingbooksaboutPHParegoodnextsteps:

ProgrammingPHP,byRasmusLerdorfandKevinTatroe
(O'Reilly).Amoredetailedandtechnicallookathowto
writePHPprograms.Includesinformationongenerating
graphicsandPDFs.
PHPCookbook,byDavidSklarandAdamTrachtenberg
(O'Reilly).AcomprehensivecollectionofcommonPHP
programmingproblemsandtheirsolutions.
EssentialPHPTools,byDavidSklar(Apress).Examplesand
explanationsaboutmanypopularPHPadd-onlibrariesand
modulesincludingHTML_QuickForm,SOAP,andtheSmarty
templatingsystem.
UpgradingtoPHP5,byAdamTrachtenberg(O'Reilly).A
comprehensivelookatthenewfeaturesofPHP5,including
coverageoffeaturesforXMLhandlingandobject-oriented


programming.
Thesebooksarehelpfulforlearningaboutdatabases,SQL,and
MySQL:
WebDatabaseApplicationswithPHP&MySQL,byDavid
LaneandHughE.Williams(O'Reilly).HowtomakePHPand
MySQLsinginharmonytomakearobustdynamicwebsite.
SQLinaNutshell,byKevinE.Kline(O'Reilly).The
essentialsyouneedtoknowtowriteSQLqueries.Covers
theSQLdialectsusedbyMicrosoftSQLServer,MySQL,
Oracle,andPostgreSQL.
MySQLCookbook,byPaulDuBois(O'Reilly).A
comprehensivecollectionofcommonMySQLtasks.
MySQLReferenceManual
(Theultimatesourcefor

informationaboutMySQL'sfeaturesandSQLdialect.
ThesebooksarehelpfulforlearningaboutHTMLandHTTP:
HTML&XHTML:TheDefinitiveGuide,byBillKennedyand
ChuckMusciano(O'Reilly).Ifyou'vegotaquestionabout
HTML,thisbookanswersit.
DynamicHTML:TheDefinitiveReference,byDanny
Goodman(O'Reilly).Fullofusefulinformationyouneedif
you'reusingJavaScriptorDynamicHTMLaspartoftheweb
pagesyourPHPprogramsoutput.
HTTPDeveloper'sHandbook,byChrisShiflett(Sams
Publishing).Withthisbook,you'llbetterunderstandhow


yourwebbrowserandawebservercommunicatewitheach
other.
Thesebooksarehelpfulforlearningaboutsecurityand
cryptography:
WebSecurity,Privacy&Commerce,bySimsonGarfinkel
(O'Reilly).Areadableandcompleteoverviewofthevarious
aspectsofweb-relatedsecurityandprivacy.
PracticalUnix&InternetSecurity,bySimsonGarfinkel,
AlanSchwartz,andGeneSpafford(O'Reilly).Aclassic
explorationofallfacetsofcomputersecurity.
AppliedCryptography,byBruceSchneier(JohnWiley&
Sons).Thenittygrittyonhowdifferentcryptographic
algorithmsworkandwhy.
Thesebooksarehelpfulforlearningaboutsupplementarytopics
thatthisbooktouchesonlikeXMLprocessingandregular
expressions:
LearningXML,byErikT.Ray(O'Reilly).Wheretogofor

morein-depthinformationonXMLthanChapter11.
LearningXSLT,byMichaelFitzgerald(O'Reilly).Yourguide
toXMLstylesheetsandXSLtransformations.
MasteringRegularExpressions,byJeffreyE.F.Friedl
(O'Reilly).Afteryou'vedigestedAppendixB,turntothis
bookforeverythingyoueverwantedtoknowaboutregular
expressions.


ConventionsUsedinThisBook
Thefollowingprogrammingandtypesettingconventionsare
usedinthisbook.

ProgrammingConventions
ThecodeexamplesinthisbookaredesignedtoworkwithPHP
5.0.0.TheyweretestedwithPHP5.0.0RC2,whichwasthe
mostup-to-dateversionofPHP5availableatthetimeof
publication.AlmostallofthecodeinthebookworkswithPHP
4.3aswell.ThePHP5-specificfeaturesdiscussedinthebook
areasfollows:
Chapter7:themysqlifunctions
Chapter10:thefile_put_contents()function
Chapter11:theSimpleXMLmodule
Chapter12:theE_STRICTerror-reportinglevel
Chapter13:somenewfeaturesrelatedtoclassesand
objects,theadvancedXMLprocessingfunctions,the
bundledSQLitedatabase,andthePerlextension

TypographicalConventions
Thefollowingtypographicalconventionsareusedinthisbook:

Italic
Indicatesnewterms,exampleURLs,exampleemail
addresses,filenames,fileextensions,pathnames,and
directories.

Constantwidth
Indicatescommands,options,switches,variables,
attributes,keys,functions,types,classes,namespaces,
methods,modules,properties,parameters,values,objects,
events,eventhandlers,XMLtags,HTMLtags,macros,the
contentsoffiles,ortheoutputfromcommands.

Constantwidthitalic
Showstextthatshouldbereplacedwithuser-supplied
values.

Thisiconsignifiesatip,suggestion,orgeneralnote.

Thisiconindicatesawarningorcaution.


UsingCodeExamples
Typingsomeoftheexampleprogramsinthebookyourselfis
instructivewhenyouaregettingstarted.However,ifyour
fingersgetweary,youcandownloadallofthecodeexamples
from />Thisbookisheretohelpyougetyourjobdone.Ingeneral,you
mayusethecodeinthisbookinyourprogramsand
documentation.Youdonotneedtocontactthepublisherfor

permissionunlessyou'rereproducingasignificantportionofthe
code.Forexample,writingaprogramthatusesseveralchunks
ofcodefromthisbookdoesnotrequirepermission.Sellingor
distributingaCD-ROMofexamplesfromO'Reillybooksdoes
requirepermission.Answeringaquestionbycitingthisbook
andquotingexamplecodedoesnotrequirepermission.
Incorporatingasignificantamountofexamplecodefromthis
bookintoyourproduct'sdocumentationdoesrequire
permission.
Weappreciate,butdonotrequire,attribution.Anattribution
usuallyincludesthetitle,author,publisher,andISBN.For
example:"LearningPHP5byDavidSklarCopyright2004
O'ReillyMedia,Inc.,0-596-00560-1."Ifyoufeelyouruseof
codeexamplesfallsoutsidefairuseorthepermissiongiven
above,feelfreetocontactthepublisherat



CommentsandQuestions
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Acknowledgments
Thisbookistheendresultofthehardworkofmanypeople.
Thankyouto:
Themanyprogrammers,testers,documentationwriters,
bugfixers,andotherfolkswhosetime,talent,anddevotion
havemadePHPthefirst-classdevelopmentplatformthatit
istoday.Withoutthem,I'dhavenothingtowriteabout.
TheAppleWWPMHardwarePlacementLabfortheloanof
aniBook,andtoAdamTrachtenberg,GeorgeSchlossnagle,
andJeremyZawodnyforadviceonsomecodeexamples.
Mydiligentreviewers:GriffinCherry,FlorenceLeroy,Mark
Oglia,andStewartUgelow.Theycaughtplentyofmistakes,
turnedconfusingexplanationsintoclearones,and
otherwisemadethisbookfarbetterthanitwouldhave
beenwithoutthem.
RobertRomano,whoturnedmyblockydiagramsandrustic
pencilsketchesintohigh-qualityfiguresandillustrations.
TatianaDiaz,whofunneledallofmyrandomquestionsto
therightpeople,keptmeonschedule,andultimatelymade
surethatwhateverneededtogetdone,wasdone.

NatTorkington,whoseeditorialguidanceandhelpful
suggestionsimprovedeverypartofthebook.WithoutNat's
feedback,thisbookwouldbetwiceaslongandhalfas
readableasitis.
Forabetterfatethanwisdom,thankyoualsotoSusannah,


withwhomIenjoyignoringthesyntaxofthings.


Chapter1.OrientationandFirstSteps
Therearelotsofgreatreasonstowritecomputerprogramsin
PHP.MaybeyouwanttolearnPHPbecauseyouneedtoput
togetherasmallwebsiteforyourselfthathassomeinteractive
elements.PerhapsPHPisbeingusedwhereyouworkandyou
havetogetuptospeed.Thischapterprovidescontextforhow
PHPfitsintothepuzzleofwebsiteconstruction:whatitcando
andwhyit'ssogoodatwhatitdoes.You'llalsogetyourfirst
lookatthePHPlanguageandseeitinaction.