Babban matsala tare da auna lokacin gudanar da aikin shine yana iya zama da wahala a tantance tsawon lokacin da wani aiki ke ɗauka don aiwatarwa. Hakan ya faru ne saboda lokacin da aikin ke ɗauka yana iya dogara ne akan abubuwa daban-daban, waɗanda suka haɗa da girma da rikitarwar aikin, kwamfutar da ake aiwatar da ita, da saurin na'urar sarrafa kwamfuta.
There are many ways to measure the run time of a function in JavaScript. One way is to use the Date object:
function measureFunctionRunTime(func) { var start = new Date().getTime(); func(); var end = new Date().getTime(); return end - start; }
1. Wannan aikin yana ɗauka a cikin ma'auni mai suna "func" wanda shine aiki.
2. Sannan ya haifar da sabon abu na kwanan wata kuma yana samun lokacin a cikin millise seconds (getTime()). Wannan shine lokacin farawa.
3. Sannan yana gudanar da aikin da aka shige shi azaman siga.
4. Yana haifar da wani sabon abu kwanan wata kuma ya sake samun lokacin a cikin millise seconds (getTime()). Wannan shine lokacin ƙarshe.
5. A ƙarshe, yana mayar da bambanci tsakanin ƙarshen lokacin da lokacin farawa (ƙarshen - farawa). Wannan yana baka lokacin gudu na aikin a cikin millise seconds.
Nau'in Ƙungiyar
Akwai nau'ikan ƙungiyoyi uku a cikin JavaScript: m, sako-sako, da bayyane.
Ƙungiyoyi masu tsattsauran ra'ayi sune mafi ƙuntatawa. Suna ba da izinin nau'in nau'i ɗaya kawai don haɗawa da wani nau'in nau'in. Misali, ƙaƙƙarfan haɗin kai tsakanin lamba da kirtani kawai zai ba da damar haɗa lamba tare da kirtani. Ƙungiyoyin da ba su da ƙarfi ba su da ƙuntatawa fiye da tsauraran ƙungiyoyi. Suna ba da damar kowane nau'ikan abubuwa guda biyu su haɗu, muddin haɗin yana da ma'ana. Misali, saƙon haɗin kai tsakanin lamba da kirtani na iya haɗawa da lambobi da alamomi. Ƙungiyoyin fayyace su ne mafi ƙarancin ƙuntatawa na ƙungiyar. Suna ba da izinin haɗa kowane nau'in sinadari da kowane nau'in sinadari, ba tare da tantance nau'in ƙungiyar ba. Misali, haɗin kai da ke tsakanin lamba da kirtani na iya haɗawa da lambobi da alamomi.
buga
Buga a JavaScript ya ɗan bambanta da bugawa a cikin wasu harsuna. A cikin JavaScript, ba kwa buƙatar buga cikakken kalmar maɓalli ko sunan aiki. Za ka iya kawai rubuta harafin farko na keyword ko aiki kuma sauran kalmar za a cika ta atomatik.
Misali, idan kuna son rubuta “aiki”, zaku rubuta “f” kawai kuma JavaScript zai cika maka sauran kalmar. Idan kana son rubuta “jijjiga”, za ka rubuta “a” kawai kuma JavaScript zai cika maka sauran kalmar.
Nau'in Alamu
Nau'in alamu wani sigar harshen JavaScript ne wanda ke ba ka damar tantance nau'in magana ba tare da amfani da nau'in afareta ba. Misali, lambar mai zuwa tana bayyana cewa m x lamba ce:
var x = 5;
Hakanan zaka iya amfani da nau'in alamu lokacin da kake bayyana aiki. Misali, lambar da ke biyowa tana bayyana aikin da ke ɗaukar ma'aunin shigarwa na nau'in lamba kuma ya dawo da kirtani:
aikin ninka (x) {dawo x * x; }
