PHP dlaim: chav kawm ntawv Piv txwv li creation

Lub tswv yim ntawm yam khoom-taw qhia kom paub programming yog npaum li cas nrug possibilities PHP vim hais tias ntawm nws cov tseem, tab sis txawm nyob rau hauv lub tam sim no siv nws muab lub programmer unlimited possibilities. PHP dlaim tsim - ib tug tshwj xeeb txoj kev ntawm ib tug hauv chav kawm ntawv (kwv) uas yog hu ua txhua lub sij hawm ib tug piv txwv yog tsim.

Txwv no yog hais tias PHP yog ua hauj lwm thaum lub sij hawm ntawm ib sab. Nyob rau ib lub sij hawm thaum cov nplooj yog refreshed los yog loaded lwm nplooj ntawv rau cov tib qhov chaw, qhov yuav tsum tau system khoom tsim dua ntawm kos.

Tsim ib tug piv txwv

Class hauj lwm yog tsis yuav tsum tau muaj ib tug constructor. Yog hais tias koj xav tau los npaj rau thawj zaug qhov tseem ceeb ntawm ntau yam, mus caum lub sij hawm ntawm tsim cov chav kawm ntawv Piv txwv li (kwv) mus ua tej yam rau lwm yam khoom, koj yuav siv tsis tau PHP chav kawm ntawv dlaim syntax thiab sau rau qhov tsim nyog code sab nraum lub chav kawm ntawv txoj kev.

Raws li cov logic kwv-taw qhia kom paub programming style, txhua chav kawm yuav tsum tau muaj ib tug constructor tias ntau yuav tsum tau pib los ntawm cov chav kawm ntawv tsob ntoo abstract (li lawm) txwv zeej txwv koob. Qhov no tej yam qub qab ntawm yav dhau los, es ib tug paub tab paub xav xyaum.

Thaum pedigree pib tseem ceeb hauv chav kawm ntawv, uas muaj nws tus kheej cov ntaub ntawv thiab cov khoom txuam nrog rau lwm cov ntaub ntawv (khoom) tsis muaj nuj nqi tsim PHP yog indispensable.

Nyob rau hauv qhov kev piv txwv, cov kev ua (constructor) yog hu ua los tsim (PHP dlaim) hnub ntawm cov chav kawm ntawv Piv txwv li. Nws muaj ib tug meej lub npe thiab yog hu ua __construct tshuab ib zaug xwb, thaum cov chav kawm ntawv Piv txwv li yog tsim.

Qhov no hauv chav kawm ntawv muab ib tug zoo li qub kuj tsis paub meej $ iUniqueNo, uas nyob rau hauv txhua txhua daim ntawv luam ntawm cov hoob kawm no yuav muaj ib tug tshwj xeeb muaj nqis. Tej lub sij ntawm cov chav kawm ntawv muaj tsis muaj dab tsi nyob rau hauv ntau tsuas yog rau cov hauj lwm nyob rau hauv lub PHP lub moj khaum thiab syntax yog muab los ntawm tus tsim tawm ntawm lawv sis txoj kev.

Qub txeeg qub teg initialization logic

Txhua yam khoom yuav tsum siv nws cov hom phiaj, muaj dab tsi nws yuav tsum, thiab ua li cas kuv yuav tsum tau. Nrog xws li ib tug tsim nyog foundations initialization nyob rau txhua theem poj koob yawm txwv tej zaum yuav muaj xws li initialization ntawm txhua txwv zeej txwv koob, xeeb leej xeeb ntxwv hu ua ib theem.

Nyob rau hauv qhov kev piv txwv, cov lo lus tseem ceeb tso cai rau koj yuav tau hu rau niam txiv :: niam txiv constructor nrog rau theem ntawm cov me nyuam. Semantics yog yooj yim. Thawj yog ua nws initialization txwv zeej txwv koob, ces tam sim no lom. Tus thawj li nram no nws tus kheej logic, lub thib ob - nws tus kheej.

Thaum txhua tus kwv yog koom nyob rau hauv lub lag luam, lub zuag qhia tag nrho cov txheej txheem yog muaj tseeb thiab to taub. Tab sis qhov no yuav tsum tsis txhob yuav feem ntau kev raws li lub cai rau tas nrho cov chaw nruab.

Pedigree system khoom "zaub mov" nyob rau hauv thawj approximation yuav muaj ib yam dab tsi nyob rau hauv ntau, tab sis cov khoom yog mis nyuj, dib liab, cov nplej zom thiab cereals txawm hais tias lawv yuav mus rau xws li ib tug system, tab sis lawv saib thiab yog qhia heev txawv.

Tsim tawm yuav tsum tau tsim txhua yam khoom nyob rau hauv daim ntawv thov system, thiab tsis nyob rau yuav ua li cas nws yog ib zaug ib tug neeg pom tias. Txhua teeb meem yog nws, nws yog ib tug yuav tsum tau siv nyob rau hauv PHP niam txiv dlaim - tsis txog.

Pej xeem thiab tsoom constructors

Lub neej ntawd constructor yog ib qho thiab muaj rau siv los ntawm tag nrho cov xeeb leej xeeb ntxwv. Tsis tas qhia pej xeem muaj nuj nqi dlaim, los ntawm neej ntawd hais, PHP khoom tag nrho piav raws li ntau.

Yuav ua li cas nws yuav ua rau kev txiav txim zoo siv cov private lo lus tseem ceeb nyob rau hauv qhov kev piav qhia ntawm lub designers - lub tseem ntawm qhov teeb meem, ib tug feature ntawm tus txheej txheem ntawm txoj kev loj hlob los yog programmer nyiam?

Los ntawm ib tug conceptual pom pedigree khoom tej zaum yuav tso cai rau tej kev txwv nrog rau lawv tus pog koob yawg koob rau xeeb leej xeeb ntxwv, tab sis ntau npaum li cas yog ib tug tsim nyog logic yog ib qho nyuaj rau hais tias, lawm, nyob rau hauv lub zuag qhia tag nrho cov ntsiab lus teb.

Nruas lub neej

Lub tswvyim ntawm cov kwv-taw qhia kom paub programming PHP dlaim chav kawm ntawv wider cib fim rau cov yooj yim yog vim li cas hais tias cov tom kawg tsuas muaj nyob rau ntawm lub sij hawm ntawm ib sab, nws rov tsim los yog tsim lwm page.

Kev Koom Tes ntawm JavaScript AJAX browser thiab cov code rau cov neeg rau zaub mov yuav pab tau sim haum lub neej ntawm cov khoom, tab sis nyob rau hauv tej daim ntawv nws yuav tsawg style.

PHP muab lub peev xwm los khiav lub tsab ntawv rau lub neeg rau zaub mov thaum tus neeg yog "kaw" thiab "txais" tus neeg rov qab mus rau hauv tsab ntawv khiav lawv ua ntej, tiam sis qhov no yog tsis ib qho kev xaiv thaum uas yam khoom-taw qhia kom paub cov kev pab cuam yog siv nyob rau hauv C ++.

Nyob rau hauv lub caij nyoog kawg no, koj muaj peev xwm tsim ib tug ua tiav system ntawm cov khoom uas yuav tau "mus ib txhis", raws li qhov kev pab cuam yog li thiab running. Txawm li cas los, nws tsuas muaj peev xwm khav ib tug ruaj ruaj hom lus programming zoo li C ++, C #, Pascal & Delphi. tag nrho cov ua txawv, nyob sai thiab nce mus txog ntau nyob rau hauv ib tug dynamic online ntiaj teb no.

Los ntawm cov serialization ntawm nws tus kheej-preservation

Koj yuav nrhiav tau cov keeb kwm ua neeg ncajncees rau lub sij hawm "serialization" thiab cov tsos nyob rau hauv lub neej txhua hnub lub tswvyim ntawm "khawv koob txoj kev". Tab sis txhua yam yog yooj yim npaum li. Raws nraim tib yam li qhov txawv ntawm txoj kev ywj pheej ntawm lub C ++ rau cov hardness ntawm lub C # serialization txawv los ntawm lub banal lub tswv yim:

• sau tus kwv mus rau ib tug hlua;
• nyeem ib tug kwv los ntawm ib txoj hlua.

Hais tias surround khawv koob thiab mythical tej yam yees siv txoj kev - zoo nkauj, nrov nrov, tab sis me ntsis tswv yim. Lub ntiaj teb no ntawm cov ntaub ntawv yog nthuav feem ntau nyob rau hauv uas tag nrho cov pom, audible thiab tangible yuav piav raws li tej yam yooj yim thiab to taub cov ntawv nyeem.

Cov ntaub ntawv yeej ib txwm tau, yog thiab yuav ua tau ib tug cim hlua. Tsis muaj teeb meem dab tsi qhov. Lub formal lug ntawm programming lus, lub cim ntawm cov xwm nyob ib leeg - coding rooj.

Lub tswv yim ntawm converting ib tug kwv rau hauv ib txoj hlua thiaj li hais tias thaum tsim nyog, nws twb tau rov qab los ntawm no kab tsis poob lub essence - ib tug heev lub tswv yim.

Los ntawm nws tus kheej rau nws tus kheej

Semantics PHP dlaim constructor nyob rau hauv nws syntax yog tsawg, tab sis yog hais tias tus designer tsim nrog cov tsim txoj hauj lwm:

• Nws yog qhov pib - los ua ib tug lig tshiab Piv txwv li;
• yog tam sim no lub xeev - ib qho uas twb muaj lawm Piv txwv li.

PHP txwv vim lub fact tias cov system ntawm cov khoom nws tshwm sim tsuas yog thaum lub sij hawm ntawm ib sab, lawv thim lawv tus kheej.

Tsim ib tug system ntawm cov khoom nyob rau hauv lub tsim ntawm nplooj ntawv nyob rau koj qhov chaw, koj muaj peev xwm cawm tau nws. Rau simplicity, tus txheej txheem no yog tsis tas hu ua serialization, peb yuav txwv tsis pub lub preservation ntawm tus txheej xwm quo (database ntaub ntawv), thiab thaum twg yuav tsum tau mus reconvene tib yam page los yog tsim lwm nyob rau hauv tib qhov chaw, tsuas yog los rau tam sim no lub xeev ntawm tej xwm txheej, uas muaj twb tau tsim.

Nyob rau hauv qhov ntsiab lus teb, tus kwv system yog tsim tsuas yog ib zaug, thiab nyob rau hauv lub chav kawm ntawm lub site nws yog cia li tsim. Nyob rau hauv no cov tswvyim, koj muaj peev xwm tsim ib tug system ntawm cov khoom raws li ua adaptable mus hloov tej yam kev mob.

Self-perpetuating system kwv "nco" ua hauj lwm ntawm cov qhua thiab cov xwm txheej page, thiab txhua lub sij hawm peb khiav PHP, nws tsis yog tsim los ntawm kos thiab rov qab mus rau lub yav dhau los lub xeev.