An warware: saitin wakili

Proxy a cikin JavaScript babban kayan aiki ne wanda masu haษ“akawa ke amfani da shi don keษ“ance ษ—abi'a da aiki don wani abu. Wannan abu yana iya haษ—awa da jeri, ayyuka, ko wasu abubuwa kuma. Ana amfani da shi don ayyuka kamar gano binciken kadarori, ษ—awainiya, ฦ™ididdigewa, kiran aiki, da ฦ™ari mai yawa.

Fahimtar wakili

Da farko dai, muna bukatar mu zurfafa cikin ra'ayi na Proxy a cikin JavaScript. Proxy wani abu ne a cikin JavaScript wanda ke ษ—aukar wani abu, wanda kuma aka sani da manufa. Yanzu, wannan wakili na iya tsoma baki tare da duk ayyukan da ake nufi da manufa, yana ba mu damar amfani da halayen al'ada gare shi. Wannan ya haษ—a da binciken kadarori, ษ—awainiya, ฦ™ididdigewa, kiran aiki da sauransu.

ฦ˜irฦ™irar wakili abu ne mai sauฦ™i. Duk abin da kuke buฦ™ata shine maษ“allin 'sabon' tare da 'Proxy' wanda ke biye da gardama biyu: abin da ake nufi da abu mai kulawa. Abun mai sarrafa ya haษ—a da abin da ake kira tarkuna, waษ—anda ainihin su ne hanyoyin ayyana ayyukan ษ—abi'a na al'ada.

Saita Proxy

Ta yaya daidai, to,, muke saita wakili a JavaScript? Ga bayanin mataki-mataki:

let targetObject = {
 key: 'I am the target'
};

let handlerObject = {
 get: function(target, prop, receiver) {
  return `Proxy for ${prop}`;
 }
};

let proxyObject = new Proxy(targetObject, handlerObject);

console.log(proxyObject.key);  // Output: Proxy for key

Wannan rubutun mai sauฦ™i ya saita wakili ta amfani da manufa da abin sarrafawa. Hakanan, kamar yadda zaku iya lura, ana bayyana tarkon samun a cikin mai sarrafa. Yana katse hanyar shiga dukiya ("samun") kuma ya dawo da kirtani maimakon ainihin kadarorin daga abin da aka yi niyya.

Dacewar Wakilci a cikin JavaScript

Proxy a cikin JavaScript kayan aiki ne mai ฦ™arfi da gaske. Waษ—annan proxies suna ba mu damar:

  • Tabbatar da kaddarorin kafin ฦ™ara su zuwa abun
  • Tsaya canje-canje zuwa wasu abubuwa
  • Gina sababbin APIs
  • ฦ˜irฦ™iri nau'ikan tarin abubuwa daban-daban
  • ...

A taฦ™aice, Proxy a cikin JavaScript yana ba mai amfani daษ—aษ—ษ—en iko akan abubuwan su, wanda ke haifar da mafi tsabta da ingantaccen shirye-shirye. Duk da haka, ya kamata a lura cewa fahimta da aiwatar da proxies yana buฦ™atar zurfin sanin yadda JavaScript ke aiki. Don haka, ya kamata a yi tunani mai kyau game da amfani da shi, musamman don aikace-aikace masu rikitarwa.

Dakunan karatu na gama gari da Ayyuka

Yayin da JavaScript yana ba da tallafin wakili na asali, akwai wasu ษ—akunan karatu waษ—anda zasu iya sa ma'amala da Proxies sauฦ™i ko ma ฦ™ara ฦ™arin fasali. Misalai biyu masu ban sha'awa sune Laburaren Proxy-observe, wanda ke ba da damar lura da canje-canje a cikin abubuwa, da ษ—akin karatu na Harmony-reflect wanda ke ba da dabi'a ta asali ga duk tarkuna.

Proxy hakika ra'ayi ne mai mahimmanci kuma mai amfani a cikin JS. Lokacin da aka fahimta kuma aka yi amfani da su daidai, yana da yuwuwar haษ“aka ingantaccen shirye-shirye. ฦ˜irฦ™irar wakili na iya zama kamar abin ban tsoro da farko, amma da zarar kun sami rataye shi, babu iyaka ga abin da za ku iya cimma tare da ษ—an ฦ™irฦ™ira.

Ka tuna, yin aiki ya zama cikakke, kuma duniyar JavaScript Proxies ba ta wuce ฦดan rubutun ba!

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