JavaScript-tsararru da halittarsa. All game da JavaScript iri-iri

A cikin wannan labarin za muyi la'akari da jigon JavaScript, abubuwan da aka gyara. Javascript shine harshen rubutattun harshe wanda aka tsara don tsarawa. A gaskiya, yana amfani da harshen ECMAScript (ECMA-262 misali).

Ina ake amfani da JavaScript? An yi amfani dashi azaman harshe wanda aka sanya don ya ƙayyade hanya ta software zuwa abu na aikace-aikacen. Ana iya samuwa a cikin masu bincike: an yi amfani dashi a matsayin harshen rubutun da yake ba da hulɗar yanar gizon yanar gizo.

Mafi muhimmancin siffofin gine-ginen samfurin wannan samfurin yana da tsayayyewa da rashin ƙarfi, da sarrafawa ta atomatik, kayan aiki na kwarai, ayyuka waɗanda suke da abubuwa na farko.

Gaba ɗaya, Javascript ya rinjayi dalilai daban-daban, domin a cikin ci gaba da suke so su ƙirƙirar harshe kamar Java, amma sauƙi don amfani da masu shirye-shirye. By hanyar, harshen JavaScript ba mallakar wani sha'anin ko kungiyar, abin da ya sa shi sabanin yawan software styles amfani da yanar gizo developers.

Ya kamata a lura cewa JavaScript ita ce alamar kasuwanci mai rijista na Oracle Corporation.

Menene tsararraki?

Kira tsararru data type, wanda Stores ƙidãyayyu dabi'u. Kowane irin wannan darajar ana kiransa nau'in tsararraki, kuma lambar da aka haɗa abin da aka haɗa shi shine alamar. Jawabin Javascript ba shi da ƙarfi. Wannan yana nufin cewa cikakkun bayanai game da tsararrakin na iya samun kowane irin, kuma sassa daban-daban na wannan tsararren suna da nau'o'in daban daban.

Bugu da ƙari, Javascript na da ƙarfi, wanda ke nufin cewa babu buƙatar bayyana girman ƙayyadaddun. Hakika, zaka iya ƙara sababbin sassa a kowane lokaci.

Array Production

Yin amfani da harshen Javascript, ƙirƙirar tsararraki ba wuya ba ne. Akwai hanyoyi biyu don wannan. Na farko ya shafi yin tsararraki tare da madaidaiciya - ginshiƙan madauki, a ciki akwai jerin sassa, rabu da ƙira.

• Bada fadi = []; // kullin tsararru;
• Lambobi iri = [4, 1, 2, 5]; // wani tsararraki tare da nau'ikan na'ura guda biyar;
• Var bambanta [[1.5, ƙarya, "rubutu"]; // wani tsararraki tare da abubuwa uku na daban.

Yawanci, bazai buƙaci dabi'u su zama masu sauki (igiyoyi da lambobi) ba. Hakanan zai iya kasancewa wani maganganu, alal misali, rubutattun manufofi, sauran ayyuka da kayan aiki.

Hanya na biyu don ƙirƙirar tsararren shine kiran mai zane Array (). Zaka iya kira shi a hanyoyi uku:

• Kira mai zane ba tare da muhawara ba: var b - sabon Array (). A nan, an halicci tsararren tsararru wanda ya dace da ainihin ainihi [].
• Mai ginawa a bayyane yana da dabi'u na sassan kayan aikin: var b = sabon Array (1, 3, 5, 8, "string", gaskiya). A wannan yanayin, ana gabatar da mai zane tare da lissafin muhawarar da suka zama sabbin kayan aiki. Anyi jayayya ga jayayya a cikin wurin da aka ƙayyade su.
• Ma'anar yankin don haɓakar dabi'u mai kyau. Anyi wannan ta hanyar ƙayyade jerin tsararren lamba guda ɗaya da aka haɗa a cikin iyaye: var b = sabon Array (5). Wannan hanyar ganowa ta shafi rarrabawa zuwa jerin tsararren samfurin da ake buƙata (wanda aka lissafa a matsayin wanda ba a ƙayyade) ba tare da yiwuwar sanya halayen dabi'u a yayin gabatarwa. Irin wannan nau'i ana amfani dasu a matsayin wuri na farko wanda Javascript ya tsara wanda aka sani a gaba.

Rubuta, karantawa, da kuma ƙara bayanan tsawa

Zaka iya samun damar abubuwan da aka tsara na tsararren ta amfani da [] afareta. By hanyar, duk abubuwan da ke cikin JavaScript, farawa daga sifilin, an ƙidaya. Don samun zama dole abubuwa, nuna ta lambar a square baka. A matsayinka na mulkin, ana iya canza bayanan. Kuma don ƙara JavaScript ga tsararru, kawai sanya sabon darajar.

Ya kamata a lura cewa a cikin zane na JavaScript za ka iya adana duk wasu abubuwa na kowane irin.

Length na tsararru

Don haka, mun san abin da JavaScript yake. Tsawancin jinsin shine al'ada mai ban sha'awa. Bari muyi la'akari da shi a cikin daki-daki. Duk kayan aiki, waɗanda aka tsara tare da taimakon mai tsara Array (), kuma sun gano ta hanyar tsararru, suna da ƙayyadaddun ɗakin da suke tunawa da adadin abubuwan da aka ajiye. Tun da akwai bayanan da ba a bayyana ba a cikin tsararrakin (ƙididdigar ba tare da cikakke ba), kalmar da ta fi dacewa ta zama kamar wannan: yawancin tsawon lokaci kullum ya fi girma fiye da ɗaya daga cikin mafi yawan lamba (index) na bangaren mahaɗin. An daidaita madaidaicin ingancin ta atomatik, ya kasance daidai lokacin da sababbin sassa suka bayyana a cikin tsararren.

Don nuna bangaren ƙarshe na tsararren, za ka iya amfani da dukiya tsawon.

Ƙarshen daki-daki yana da alaƙa ɗaya wanda bai fi girman girman tsararren ba. Bayan haka, ƙidaya yana fara koyaushe daga karce. Oh, wannan Javascript! Tsawon tsararren ya dogara da ainihin abubuwa. Don haka idan ba ku san yawancin su ya kamata ba, amma kuna buƙatar komawa zuwa ɓangaren haɗin tsararren, kuna buƙatar shigar da shigarwa: v.ngth - 1.

Array na tsararrun bayanai

Sau da yawa ana amfani da dukiya tsawon lokaci don ƙididdige bayanai game da tsararraki a madauki:

• Yawan iri = ["strawberry", "peach", "apple", "banana"];
• Don (var I = 0; i
• Rubuta.write ('ya'yan itatuwa) "" ... ").

A cikin wannan misali, yana nuna cewa an sanya sassan da aka ci gaba da farawa tare da ɓangaren farko wanda ke da alamar tauraron. Idan wannan ba haka bane, kafin a kira kowane ɓangare na tsararren, dole ne a bincika ko an bayyana shi.

Ana amfani da maƙalli a wasu lokutan don farawa matakan.

Ƙarawa da ƙaddamar da tsararraki

Ina mamaki yadda ake yin amfani da harshe na Javascript a cikin tsararren don ƙara? A cikin aiwatar da aiki tare da kayan aiki, tsawon tsawon tsayi mai kyau ya inganta, wanda shine dalilin da ya sa dole mu kula da wannan kanmu. Wajibi ne a tuna da daki-daki daya: yawancin dukiya ba kawai za a iya karantawa ba, har ma don rubutawa. Idan an ƙayyade tsawon ƙimar darajar da ba ta da daraja ga girman halin yanzu, to, tsararren yana rage zuwa darajar da aka ƙayyade. Duk wani ɓangaren da ba a cikin sabon kewayon alamomi ba shi da haɗi, kuma lambobin su sun ɓace, koda kuwa daga bisani sun dawo da baya - ba a dawo da dabi'u ba.

Yana da sauƙi a share tsararraki kamar wannan: matsala = 0.

Idan inganci na tsawon ya fi girma a yanzu, a ƙarshen tsararren, sabon ɓangarorin da ba a shigar ba sun bayyana, wanda zai ƙara shi zuwa girman da ake so.

Share bayanan tsabta

Mai tafiyar da afareta yana ƙayyade ƙimar da ba a ƙayyade ba a bangaren jigilar, kuma yana ci gaba da zama. Idan kana so ka share wani ɓangaren Javascript na Javascript don sauran cikakkun bayanai sun koma wurin sarari, kana buƙatar amfani da ɗaya daga cikin hanyoyin da za a iya gani. Hanyar Array.shift () yana kawar da sashi na farko, pop () shine sashe na ƙarshe, kuma hanya ta splice () ita ce ɗaya ko jerin abubuwan da aka gyara a ko'ina a cikin tsararren.

Gudun hanyoyi da yawa

Da alama cewa mun fahimci kadan, abin da JavaScript. Girman abubuwa guda biyu - wancan ne abin da ake buƙatar ɗauka kara. Kuna tuna cewa wadannan abubuwa na JavaScript zasu iya ƙunsar wasu abubuwa kamar yadda aka gyara? Ana amfani da wannan yanayin don samar da tashoshin multidimensional. Don ziyarci abubuwan da aka gyara a jerin tsararraki, ya isa ya yi amfani da buƙatun madauki sau biyu.

Abubuwan hulɗa

Kuma yanzu za mu koyi yadda yadda ake amfani da kayan aiki na kasuwanci na JavaScript. Don haka, muna bukatar mu dubi ka'idar: ana kiran wasu kayan aiki na yau da kullum da ake amfani da su. Suna amfani da igiya maimakon alamun. Yin amfani da irin waɗannan siffofin suna kama da yin amfani da sunan dukiya ta abu mai sauki, amma a cikin wannan sigar lokacin yin aiki a cikin tsarin tsarawa. Tun da JavaScript ba ta da hanyar yin amfani da kayan aiki, an yi amfani dashi da yawa fiye da na al'ada. Ya kamata a lura cewa har yanzu zasu iya amfani dasu don adana bayanan da kuma sauƙaƙe su tuna dalla-dalla da ake bukata don samun dama.

Sakamakon Array

Yanzu kuma menene za mu koya a cikin tsarin JavaScript? Samar da tsararraki a cikin akwatin maganganu (a kan allon kulawa), da kuma nunin dabi'u na kayan aikin tsararren.

Idan shirin yana buƙatar nuna dabi'u na duk abubuwan da aka gyara, to, yana da dacewa don amfani da sanarwa. Yana da ban sha'awa cewa ana amfani da ma'auni mai mahimmanci na dokokin domin amfani da shi azaman alamomin ɓangaren mahaɗin.

Ana wanke

Domin tace fitar da JavaScript, kana bukatar ka share tsawonsa:

• Sauya myArray = [1, 2, 5, 23];
• MyArray.length = 0.

Wadannan suna nuna aiwatar da aikin bayyanawa () a cikin sashin fasaha na Prototype JavaScript:

• Share: aiki () {;
• Wannan mai tsawo = 0;
• Koma wannan;
• }.

Ƙara da Ana cire Masu Haɗin

To, muna ci gaba da nazarin wannan harshe mai ban sha'awa na JavaScript. Za'a iya share kashi na tsararren kuma an kara da su a cikin hanya ɗaya kamar yadda ake amfani dasu na wasu abubuwa. Amma akwai wasu bambance-bambance: a yayin da aka ƙara yawan kayan haɓaka, adadin tsawon zai iya canzawa, kuma lokacin da aka gyara tsawon dukiya, za'a iya kawar da halayen lambobi. Bisa mahimmanci, algorithm don kafa dabi'u na kayan aiki shine kamar haka:

• Lokacin da ka ƙara abin da ba'a sani ba na zamani ba, idan tsawon yana daidai da ko žasa da i, tsawon lokaci an ƙayyade azaman i + 1.
• Lokacin canza yanayin tsawon, ana yin waɗannan ayyuka: idan ƙimar da aka sanya ta ƙasa da zero, An jefa RangeError. Cire dukkan halaye da ƙididdiga na nau'i, waɗanda suke daidai da sabon tsawon kuma waɗanda suka fi girma.

Gaba ɗaya, cire wani ɓangare na Javascript na JavaScript ba wuya. Bayan haka, har ma da saita tsawon, kana buƙatar cire sassan "karin" daga gare shi. Saboda haka zaɓin tsaftace tsaftacewa. Idan matakan da aka sanya na sababbin tsararru don wasu dalilai bai dace ba, amma ya wajaba don warwarewar yanzu, ya isa ya sanya nauyin zero zuwa ingancinta.

Hanyar hanyoyin unshift, motsa, pop da turawa

Ko da yake an gyara kayan aikin gyaran hannu da hannu, mutane da yawa sun bada shawarar cewa kayi amfani da hanyoyin ginawa don wannan. Wannan lamari ne wanda ke tabbatar da daidai adadin tsawon ƙimar da kuma rashin izinin shiga cikin tsararren. Ta hanya, daidai tsawon zai dace da yawan abubuwan da aka gyara.

Hanyar turawa tana ɗaukar sassan canja wuri zuwa ƙarshen tsararren. Hanyoyin da aka saba amfani da su sun sake dawowa da kuma cire shi.

Bugu da ƙari, a cikin Internet Explorer a ƙarƙashin samfurin na takwas, unshift zai iya dawowa ba tare da cikakke ba, a cikin wasu masu bincike - sabon darajar tsawon. Saboda haka ya fi kyau kada ku dogara da kudaden dawowa daga unshift.

Ƙara kuma cire sassa a tsakiyar wani tsararren

Idan kana buƙatar share tsararren JavaScript, menene zan yi? An sani cewa hanyar splice yana da sa hannu Array.prototype.splice.

Yana cire daga tsararren da shareCount of components, fara da farkon. Idan fiye da muhawara guda biyu sun wuce, to, duk hujjoji na gaba a cikin tsararru an sanya su maimakon waɗanda aka shafe su. Idan farawa ya ragu, to, alamar da aka cire daga cikin farawa zai kasance daidai da tsawon + farawa. Komawa zuwa tsararren yana daga abubuwa masu nisa.

A gaskiya ma, ta yin amfani da hanyoyi, za ka iya cire matakan daga tsakiya na tsararren ko ƙara kowane lamba zuwa kowane wuri a cikin tsararren.

A cikin mafi sauki, idan kana so ka cire wani bangaren tare da nuni i, kana buƙatar ka tambayi tsararren don hanya mai tsabta tare da sigogi i da 1.

Bisa ga mahimmanci, sashe na biyu na hanyar splice ba lallai bane, amma halayyar aiki tare da gardama guda ɗaya a kowace mai bincike ya bambanta.

Alal misali, a Firefox, a cikin sababbin sauti na Opera, a Safari da Chrome, duk bayanai za a cire zuwa ƙarshen tsararren.

A cikin IE, ba za a kawar da wani ɓangare ba. A cikin sigogin farko na Opera, ba'a iya yin halayyar ba - abu daya tare da alamar farawa za a cire. Saboda haka, dole ne a sauƙaƙe a kalla abu biyu zuwa wannan hanya.

Keys

Tabbas, lokacin da kake nazarin Javascript, haɗe-haɗe masu haɗaka, kamar yadda aka ambata a baya, ba ma a manta da su ba. Wannan wani bayani ne na ainihi (ƙwaƙwalwa zuwa ɗakin ajiyar bayanai), wanda ke ba ka damar adana nau'i-nau'i na nau'i "(maɓalli, darajar)" kuma suna goyan bayan aiki na ƙara wani abu, kazalika da sharewa da kuma neman maɓallin maɓalli:

- Bincance (maɓalli).

- Sanya (darajar, maɓalli).

- Kashe (key).

Ana tsammanin cewa nau'i biyu da nau'ikan mahimmanci ba za a iya adana su a cikin tsararren shiryawa ba. A cikin biyu, k + vv an kira darajar da ke haɗe da maɓallin k. Semantics da sunayen ayyukan da ke sama a aikace-aikace daban-daban na irin waɗannan nau'ikan na iya zama daban.

Sabili da haka, aikin na FIND (maɓallin) ya dawo da darajar da aka haɗa tare da maɓallin ƙayyade, ko wani takamaiman UNDEF abu, ma'anar cewa darajar da aka haɗa tare da maɓallin ƙayyade ya ɓace. Sauran ayyuka biyu ba sa mayar da wani abu (sai dai idan aikin ya ci nasara).

Bugu da ƙari, daga ra'ayi na ƙirar, mai amfani da kayan haɗin ginin yana dacewa da shi azaman tsararren tsari wanda ba kawai ana iya amfani dasu ba ne kawai a matsayin ƙididdiga, amma har wasu nau'ikan dabi'u - alal misali, kirtani.

Ta hanyar, goyon baya ga irin wannan nau'in yana samuwa a cikin manyan harsunan software masu fassara, irin su PHP, Perl, Ruby, Python, Tcl, JavaScript, da sauransu. Ga harsuna da basu da kayan aikin ginawa don aiki tare da kayan aiki, an aiwatar da ƙididdigar yawa a cikin ɗakunan karatu.

Misali na linzamin abokan hulɗa zai iya kasancewa a tarho tarho. A cikin wannan bambance-bambancen, darajar ita ce hadarin "F. Adireshin IO +, kuma maɓallin - lambar waya. Lambar waya ɗaya yana da mashahuri ɗaya, amma mutum ɗaya zai iya mallaka lambobi da yawa.

Abubuwan hulɗa

Ya kamata a lura da cewa shahararren shahararren sun haɗa da ayyukan da suka biyo baya:

• MUTUWA - "tafiya" ta cikin dukan nau'i nau'i.
• CLEAR - share duk rubutun.
• MIN - sami biyu tare da darajar maɓallin ƙarami.
• MAX - sami ma'aurata tare da darajar mahimmanci.

A cikin bambance-bambance guda biyu da suka gabata, kana buƙatar saka aikin daidaitawa akan makullin.

Ana aiwatar da Shirye-shiryen Abubuwa

Akwai abubuwa da yawa daban-daban na shiryawa. Yin amfani da shi mafi sauƙaƙe zai iya dogara ne a kan tsararren tsararru, waɗanda aka gyara su ne nau'i-nau'i (darajar, maɓalli). Don bugun sama da search ayyuka, za ka iya shirya gyara daga cikin tsararru da wani key binciken da aiwatar da yin amfani da wani binary search. Amma wannan zai kara yawan lokaci da ake buƙata don ƙara sabon saƙo, kamar yadda ya kamata a "cirewa" abubuwan da aka tsara na tsararren don ƙulla sabon rikodin zuwa cikin jikin maras amfani.

Ayyukan da aka fi sani da aka fi sani da su sun dogara ne akan bishiyoyi daban-daban. Alal misali, a cikin ɗakin karatun C ++ na STL, ana yin taswirar taswirar ta hanyar bishiyan baki da-ja. A cikin styles Ruby, Tcl, Python daya daga cikin nau'in tebur mai amfani. Akwai wasu aikace-aikace.

Gaba ɗaya, kowane aiwatarwa yana da nasarorin da ya dace. Yana da mahimmanci cewa dukkanin ayyuka guda uku ana kashe su a matsakaici da mummunan yanayi na tsawon lokaci (O / A), inda n shine lambobin da aka adana yanzu. Don ƙayyadaddun bishiyar bincike (ciki har da bishiyoyin baki da-ja) wannan yanayin ya cika.

An sani cewa a implementations dangane zanta Tables, da talakawan lokaci aka bayyana a matsayin D (1), wanda shi ne mafi alhẽri daga cikin ayyuka dangane da search itatuwa. Hakika, wannan bai da garantin mai high-gudun yi na raba ayyukan: saka mataki lokaci a cikin mafi munin yanayi, denoted kamar yadda Ya (n). Saka tsari aka yi na dogon lokaci a lokacin da wajibi rabo kai tsororuwar, kuma akwai bukatar sake gina zanta tebur index.

Af, wadannan kalamai zanta bad cewa a kan wannan hasashe ba shi yiwuwa a yi m ƙarin mataki MAX, MIN, da kuma wani algorithm to bincika duk kubutar da nau'i-nau'i a saukowa domin ko hawa keys.