JavaScript 數(shù)組方法大全

?數(shù)組過(guò)濾器filter()方法創(chuàng)建一個(gè)新數(shù)組，其中包含通過(guò)所提供函數(shù)實(shí)現(xiàn)的測(cè)試的所有元素。stocks.filter(stock=>stock.price<1000)/*-------------------------------------------|Array.filter*-------------------------------------------|

0:{name:"Apple",price:321.85}|

1:{name:"Disney",price:118.77}|

2:{name:"Netflix",price:425.92}*/Array.mapmap()方法創(chuàng)建一個(gè)新數(shù)組，其中填充了對(duì)調(diào)用數(shù)組中每個(gè)元素調(diào)用所提供函數(shù)的結(jié)果。stocks.map(stock=>[,stock.price])/*-------------------------------------------|Array.map*-------------------------------------------|0:(2)["Apple",321.85]|1:(2)["Tesla",2471.04]|2:(2)["Disney",118.77]|3:(2)["Google",1434.87]|4:(2)["Netflix",425.92]*/數(shù)組查找find()方法返回所提供數(shù)組中滿足所提供測(cè)試函數(shù)的第一個(gè)元素的值。如果沒(méi)有值滿足測(cè)試函數(shù)，則返回undefined。stocks.find(stock=>==='Tesla')/*-------------------------------------------|Array.find*-------------------------------------------|

{name:"Tesla",price:2471.04}*/數(shù)組.somesome()方法測(cè)試數(shù)組中至少一個(gè)元素是否通過(guò)所提供函數(shù)實(shí)現(xiàn)的測(cè)試。如果在數(shù)組中找到所提供的函數(shù)返回true的元素，則返回true；否則返回false。它不會(huì)修改數(shù)組。stocks.some(stock=>stock.price<1000)/*-------------------------------------------|Array.some*-------------------------------------------|true*/stocks.some(stock=>stock.price<10)/*-------------------------------------------|Array.some*-------------------------------------------|false*/數(shù)組.everyevery()方法測(cè)試數(shù)組中的所有元素是否通過(guò)所提供函數(shù)實(shí)現(xiàn)的測(cè)試。它返回一個(gè)布爾值。stocks.every(stock=>stock.price<1000)/*-------------------------------------------|Array.every*-------------------------------------------|false*/stocks.every(stock=>stock.price<2500)/*-------------------------------------------|Array.every*-------------------------------------------|true*/Array.forEachforEach()方法為每個(gè)數(shù)組元素執(zhí)行一次提供的函數(shù)。stocks.forEach(stock=>console.log(stock))/*-------------------------------------------|Array.forEach*-------------------------------------------|Outputseachitem(stockobject)fromthearraytotheconsole|returnsvoid(akaundefined)*/數(shù)組歸約reduce()方法對(duì)數(shù)組的每個(gè)元素執(zhí)行（您提供的）reducer函數(shù)，從而產(chǎn)生單個(gè)輸出值。stocks.reduce((total,stock)=>total+stock.price,0)/*-------------------------------------------|Array.reduce*-------------------------------------------|4772.45*/letnames=['Apple','Tesla','Disney','Google','Netflix']數(shù)組.includesinclude()方法確定數(shù)組的條目中是否包含某個(gè)值，并根據(jù)需要返回true或s.includes('Apple')/*-------------------------------------------|Array.includes*-------------------------------------------|true*/names.includes('Microsoft')/*-------------------------------------------|Array.includes*-------------------------------------------|false*/Array.indexOfindexOf()方法返回在數(shù)組中可以找到給定元素的第一個(gè)索引，如果不存在則返回-1。names.indexOf('Tesla')/*-------------------------------------------|Array.indexOf*-------------------------------------------|1*/names=

['Apple','Tesla','Disney','Google','Netflix','Tesla']Array.lastIndexOflastIndexOf()方法返回在數(shù)組中可以找到給定元素的最后一個(gè)索引，如果不存在則返回-1。從fromIndex開始向后搜索數(shù)組。names.lastIndexOf('Tesla')/*-------------------------------------------|Array.lastIndexOf*-------------------------------------------|5*/數(shù)組排序sort()方法對(duì)數(shù)組的元素進(jìn)行就地排序并返回排序后的數(shù)組。默認(rèn)排序順序?yàn)樯颍趯⒃剞D(zhuǎn)換為字符串，然后比較它們的UTF-16代碼單元值序列。排序的時(shí)間和空間復(fù)雜度無(wú)法保證，因?yàn)樗Q于實(shí)現(xiàn)。names.sort()/*-------------------------------------------|Array.sort*-------------------------------------------|['Apple,'Disney','Google','Netflix','Tesla','Tesla']*/數(shù)組切片slice()方法將數(shù)組的一部分的淺表副本返回到從開始到結(jié)束（不包括結(jié)束）選擇的新數(shù)組對(duì)象中，其中開始和結(jié)束表示該數(shù)組中項(xiàng)目的索引。原始數(shù)組不會(huì)被修改。names.slice(3)/*-------------------------------------------|Array.slice*-------------------------------------------|['Netflix','Tesla','Tesla']|*/數(shù)組連接join()方法通過(guò)連接數(shù)組（或類似數(shù)組的對(duì)象）中的所有元素（用逗號(hào)或指定的分隔符字符串分隔）來(lái)創(chuàng)建并返回一個(gè)新字符串。如果數(shù)組只有一項(xiàng)，則將返回該項(xiàng)而不使用分隔符。names.join()/*-------------------------------------------|Array.join*-------------------------------------------|"Apple,Disney,Google,Netflix,Tesla,Tesla"*/names.join('-')/*-------------------------------------------|Array.join*-------------------------------------------|"Apple-Disney-Google-Netflix-Tesla-Tesla"*/names.join('\\')/*-------------------------------------------|Array.join*-------------------------------------------|"Apple\Disney\Google\Netflix\Tesla\Tesla"*/數(shù)組到字符串toString()方法返回一個(gè)表示指定數(shù)組及其元素的字符串。names.toString()/*-------------------------------------------|Array.toString*-------------------------------------------|"Apple,Disney,Google,Netflix,Tesla,Tesla"*/stocks=[

{name:'Apple',price:321.85},

{name:'Tesla',price:2471.04},

{name:'Disney',price:118.77},

{name:'Google',price:1434.87},

{name:'