PHP Practice: string Uthelekiso

PHP yi swi inkcazelo elungileyo yokuphatha. Le syntax ulwimi bubonakaliswe iseti esebenza ngokupheleleyo imisebenzi mzekelo, inkqubo string, abanini uthelekiso.

Nawuphi algorithm - ukulandelelana ukhetho kunye nezenzo. Kodwa ngaphambi kokuba wenze isigqibo, kufuneka into ukuze uthelekise into. Line - indlela kakhulu capacious, olusebenzayo nolubonakalayo ulawulo algorithm. Line - eyongeziweyo lobeko lwe ntetho data. A data - oku isifundo iphambili "anyamekele" nayiphi algorithm.

logic Ordinary "uthelekiso-isenzo"

Ngokubanzi, ulwimi enamandla typing akenzi iiyantlukwano kwiqela le-data, ezifana umgca PHP uthelekiso inani kakhulu ezahlukene. Inani - kukwayinto entle umtya, xa iqulathe amanani kuphela, ingongoma kwaye akukho uphawu olunye ukuba akukho kusetyenziswa ukumela amanani naluphi na uhlobo (ubhalo zemathematika).

Ukuba inani kontenkatsii zidibana ngokuzenzekelayo enomgca, akukho imibuzo kwaye akukho zimpazamo ezifihlakeleyo, nokuba gettype () umsebenzi unika 'elipheleleyo' okanye 'double'.

Noko ke, kukho umahluko phakathi usebenzisa is_int () kwaye is_numeric (). Okokuqala inika lo inyaniso, kuphela xa i parameter elipheleleyo, okwesibini, xa naliphi na inani okanye umtya yamanani (uhlobo bume yi 'umtya', kodwa iquka zonke notation enikiweyo zemathematika).

Lo ngumzekelo elula - umzekelo omhle indlela abasebenzi PHP string uthelekiso ( '==' '===' ... '='!) Ngaba wosondeza izimanga ezininzi. Eziguquguqukayo bangatshintsha uhlobo zabo, azisoloko amanani, kodwa phantse lonke ke kungakhokelela emgceni. Kwityala kakhulu - oko kuya kuba umtrya ongenanto.

Ngokusekelwe kungentla, a PHP Umtya uthelekiso umsebenzi yaziwa kakhulu. Yintoni kanye ukuba akhethe, ukuba isigqibo umphuhlisi. Ezininzi iinketho ezikhoyo ukuya amabinzana rhoqo.

Imida ukusebenza ekhoyo

PHP-Uthelekiso imiqolo emibini okulungileyo 'ukwenza "function strpos () - le ibiza, umzalwana othembekileyo, ukhetho practical. Ukuba ngesiphumo inombolo umsebenzi, ngoko ngokucacileyo umtya omnye ulingana kwenye okanye inxalenye enye ukuya kwenye.

Ezozinto malungana, kodwa ngokupheleleyo indlela ekunene - ukusetyenziswa amabinzana rhoqo.

Ukuba umsebenzi $ cResult = scCheckFileName ($ cStr) unika 'oyinyaniso', ngoko ke line igama vordovsky lwefayile. Uya kuba inketho enye kuphela ukwandiswa '.docx' kwaye akukho ngabalinganiswa igama: amagama, amanani neemphawu '_', '-'.

Lo msebenzi lula iguqulelwe kwezinye iintlobo iifayile: $ CPTR = '/^([a-zA-Z...0-9\-\_]{4,239})\.(html|js|css|png|jpg | docx | txt) {1} $ / u '. Olu uhlobo usinika uluhlu Best umgca yokuskena (umz, PHP Umtya uthelekiso lisetyenziswa 'ukuba layisha phezulu iifayile kwi umncedisi, kungekho ithuba imposiso igalelo ") ukwenzela html, ikloko yeyure eziyi, CSS, ...

Ukusebenzisa strpos () kunye preg_match () - ukuzibaxa izinto. Azikho ezinxulumene ngqo umba kwexesha uthelekiso. Kodwa ke umbuzo lo algorithm - ngumbandela usebenzisa indibanisela isimbo, ukusetyenziswa onke amathuba ukuze kufikelelwe isiphumo ethembekileyo ezichanekileyo.

PHP nabasebenzayo: string Uthelekiso

Arsenal ulwimi strings kuthelekiswa - emhlophe, kungekuphela nje umsebenzi uthelekisa, kodwa ukuhlanganiswa yokusetsha okanye obambeleyo ngqo. Ngaso kufuneka ungqamane ufaniso, ukusukela yokugqibela akunyanzelekanga ukuba kukhokelele ekubeni utshintsho nawuphi na umqolo. Amaxesha amaninzi kufuneka ukhethe enye okanye elinye isebe le algorithm.

Normal lobeko PHP: lenza umtya uthelekiso umsebenzi int strcmp (S1, s2).

Isiphumo umsebenzi:

• 0 - line bayalingana;
• -1 - i umtya wokuqala ngaphantsi kuneyesibini;
• 1 - ngakumbi yokuqala ngaphezu kumqolo wesibini.

Xa practice, oku kuthetha ukuba yinxalenye kumqolo wokuqala nowesibini, ukusuka apho umsebenzi PHP (uthelekiso imiqolo) isigqibo. Inguqulelo ngakumbi elinganiselweyo strpos (), kuba xa singenayo kunokwenzeka ukuba ukwazi indawo yokungena.

strcmp () umsebenzi - sensitive. Ukuba ufuna ukuthelekisa umtya-ezilukhuni, PHP inikeza strcasecmp yayo (). Le lwesivakalisi into efanayo.

Xa mkhuba bavame ukuba basebenze kunye lonke umgca, kodwa inxalenye yawo. Ngokuba lo isethi yemisebenzi PHP (umtya uthelekiso) ziquka strncmp (S1, s2, N). I Parameter yesithathu ikhankanya enze lokufanekisa kuphela N-bytes. Isiphumo yi strcmp efanayo ().

Ma, intambo kunye nokuthelekisa

Ezi phantse lonke zimelwe strings. Xa siqwalasela kwimiboniso, izinto, okanye izakhiwo data, nto nje Ukrainian lunee ntlobo ezahlukeneyo edibeneyo a izakhiwo umtya elula.

ma umtya kunye nezintlu inganikezelwa ngendlela ezisebenzisanayo. Inguqu ye uluhlu ibe umsebenzi umtya implode (uluhlu, uphawu), umzekelo: $ margins1 = implode ( ',', $ style-> getInnerMargin ()); ... le algorithm / umsebenzisi ...; $ Margins2 = implode ( ',', $ style-> getInnerMargin ()) ikuvumela ukuba ukudibanisa yonke into isikhundla indawo umtya.

Wena ke yenzeni PHP umtya uthelekiso, kwaye ngexesha: $ check = strcmp ($ margins1, $ margins2) kwaye uqinisekise ukuba algorithm okanye umsebenzisi ukuba into utshintshile (okanye hayi). Ukuba yenza uthelekiso ngendlela eqhelekileyo, kuza kufuneka ukuba ukulungisa izinto uluhlu. Kuthatha ixesha elide kwaye kube nzima ngakumbi.

Linjongo line

Nokuba ukusetyenziswa PHP mihle ngakumbi (umtya uthelekiso) lingaphunyezwa nge iimbono into ebomini.

Ingcamango yanamhlanje lwamaziko lubonisa ukuba iipropati kunye neendlela. I yangaphambili zidla amelwe ngamanani, imitya, kwimiboniso, kunye nezinye izinto. Le yokugqibela ziquka yokurekhoda ubuchule (wabeka) kumgca ekuphulukenwe nalo kwaye ukusuka kumgca (ungasifumana na).

Ngokungafaniyo ma, injongosenzi wenza umsebenzi kunye iimpawu zabo kwaye usebenzisana kunye nezinye izinto. Object "elifanelekileyo" apho iimpawu zayo ezilulutho ngokwenene algorithm lwenkqubo xa iyonke.

Lo mzuzu inika isiseko kunye nethuba ukurekhoda xa urekhoda umtya kuphela ulwazi oluyimfuneko, kunye nokufunyanwa selayini ukubuyisela zonke iipropati abasebenza kwi meko inqwenelekayo. Ngokuqhelekileyo, kuyo nayiphi into kukho ulwazi enkulu kunye nokusebenza (ixesha). Ukuphunyezwa kwale nto ikuvumela ukugcina kwimemori kuphela, isithuba kwidiski, ingxelo database, kodwa kwenza kube lula ukuba ukuthelekisa kwangalo imigca elula kwaye yechaneke ngaphezulu.

Syntax and Semantics

PHP ephuhlisa dynamically, kunye nokusebenza wayo ngokwemiqathango strings ngokuthelekisa rhoqo yaphucuka ngokwemiqathango unyango lwabo. Kodwa ke, ayikho into ethintela umbhekisi ukuhambisa iziko womxhuzulane kwingingqi semantics.

Alithandabuzeki elokuba, ukusebenza okulungileyo, kodwa usebenziso lwayo nga yatshintshelwa intsingiselo ikhowudi kwi izinto. Xa algorithm kuboniswa inkqubo yentsebenziswano phakathi kwezinto, kubonakala ngakumbi uthelekiso ulandelelwano kunye nezenzo ngokulandelelana ngqo, isimbo zoqobo.