Proxy a cikin JavaScript babban kayan aiki ne wanda masu haɓakawa ke amfani da shi don keɓance ɗabi'a da aiki don wani abu. Wannan abu yana iya haɗawa da jeri, ayyuka, ko wasu abubuwa kuma. Ana amfani da shi don ayyuka kamar gano binciken kadarori, ɗawainiya, ƙididdigewa, kiran aiki, da ƙari 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 ɗaukar 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 haɗa da binciken kadarori, ɗawainiya, ƙididdigewa, kiran aiki da sauransu.
Ƙirƙirar wakili abu ne mai sauƙi. Duk abin da kuke buƙata shine maɓallin 'sabon' tare da 'Proxy' wanda ke biye da gardama biyu: abin da ake nufi da abu mai kulawa. Abun mai sarrafa ya haɗa da abin da ake kira tarkuna, waɗanda ainihin su ne hanyoyin ayyana ayyukan ɗabi'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 sauƙi 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 ƙarfi da gaske. Waɗannan proxies suna ba mu damar:
- Tabbatar da kaddarorin kafin ƙara su zuwa abun
- Tsaya canje-canje zuwa wasu abubuwa
- Gina sababbin APIs
- Ƙirƙiri nau'ikan tarin abubuwa daban-daban
...
A taƙaice, Proxy a cikin JavaScript yana ba mai amfani daɗaɗɗen 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 buƙatar 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 ɗakunan karatu waɗanda zasu iya sa ma'amala da Proxies sauƙi ko ma ƙara ƙarin fasali. Misalai biyu masu ban sha'awa sune Laburaren Proxy-observe, wanda ke ba da damar lura da canje-canje a cikin abubuwa, da ɗakin 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 haɓaka ingantaccen shirye-shirye. Ƙirƙirar 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 ɗan ƙirƙira.
Ka tuna, yin aiki ya zama cikakke, kuma duniyar JavaScript Proxies ba ta wuce ƴan rubutun ba!
