{"id":29318,"date":"2023-07-23T16:20:19","date_gmt":"2023-07-23T08:20:19","guid":{"rendered":"https:\/\/www.juejinka.com\/?p=29318"},"modified":"2023-07-23T16:20:20","modified_gmt":"2023-07-23T08:20:20","slug":"javascript%ef%bc%9aarray-%e9%98%b5%e5%88%97-%ef%bc%881%ef%bc%89-%e9%98%b5%e5%88%97%e5%ae%a3%e5%91%8a%e5%92%8c%e5%8f%96%e5%80%bc","status":"publish","type":"post","link":"https:\/\/www.juejinka.com\/y\/29318.html","title":{"rendered":"JavaScript\uff1aArray \u9635\u5217 \uff081\uff09 \u9635\u5217\u5ba3\u544a\u548c\u53d6\u503c"},"content":{"rendered":"\n<h2><span class=\"ez-toc-section\" id=\"Array_%E9%98%B5%E5%88%97\"><\/span>Array \u9635\u5217<span class=\"ez-toc-section-end\"><\/span><\/h2><div id=\"ez-toc-container\" class=\"ez-toc-v2_0_53 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title \" >\u76ee\u5f55<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\" role=\"button\"><label for=\"item-6a09c6b14cbfb\" ><span class=\"\"><span style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input aria-label=\"Toggle\" aria-label=\"item-6a09c6b14cbfb\"  type=\"checkbox\" id=\"item-6a09c6b14cbfb\"><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#Array_%E9%98%B5%E5%88%97\" title=\"Array \u9635\u5217\">Array \u9635\u5217<\/a><ul class='ez-toc-list-level-3'><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#%E5%AE%A3%E5%91%8A%E9%98%B5%E5%88%97\" title=\"\u5ba3\u544a\u9635\u5217\">\u5ba3\u544a\u9635\u5217<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E4%B8%AD%E6%9F%90%E4%B8%AA%E5%80%BC\" title=\"\u53d6\u5f97\u9635\u5217\u4e2d\u67d0\u4e2a\u503c\">\u53d6\u5f97\u9635\u5217\u4e2d\u67d0\u4e2a\u503c<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#Arraylength_%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E9%95%BF%E5%BA%A6\" title=\"Array.length \u53d6\u5f97\u9635\u5217\u957f\u5ea6\">Array.length \u53d6\u5f97\u9635\u5217\u957f\u5ea6<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E4%B8%AD%E6%89%80%E6%9C%89%E5%80%BC\" title=\"\u53d6\u5f97\u9635\u5217\u4e2d\u6240\u6709\u503c\">\u53d6\u5f97\u9635\u5217\u4e2d\u6240\u6709\u503c<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#ArrayisArray_%E5%88%A4%E6%96%AD%E6%98%AF%E5%90%A6%E4%B8%BA%E9%98%B5%E5%88%97\" title=\"Array.isArray \u5224\u65ad\u662f\u5426\u4e3a\u9635\u5217\">Array.isArray \u5224\u65ad\u662f\u5426\u4e3a\u9635\u5217<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.juejinka.com\/y\/29318.html\/#%E9%98%B5%E5%88%97%E5%9E%8B%E6%80%81%E8%BD%AC%E6%8D%A2\" title=\"\u9635\u5217\u578b\u6001\u8f6c\u6362\">\u9635\u5217\u578b\u6001\u8f6c\u6362<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n\n\n\n\n<p>\u5728\u524d\u9762\u4ecb\u7ecd\u53d8\u91cf\u578b\u6001\u65f6\u6211\u4eec\u6709\u63d0\u5230\u9635\u5217\uff0c\u9635\u5217\u662f\u4e00\u4e2a\u6709\u987a\u5e8f\u6027\u7684\u5e8f\u5217\uff0c\u53ef\u4ee5\u50a8\u5b58\u591a\u4e2a\u503c\uff0c\u683c\u5f0f\u4e3a \uff0c\u6bcf\u4e2a\u503c\u7167\u987a\u5e8f\u90fd\u4f1a\u6709\u5bf9\u5e94\u7684\u7d22\u5f15\uff0c\u7d22\u5f15\u4ece 0 \u5f00\u59cb\uff0c\u5ba3\u544a\u540e\u82e5\u8981\u53d6\u503c\u9700\u8981\u900f\u8fc7\u7d22\u5f15\uff0c\u4e0b\u9762\u6709\u8ba9\u6211\u4eec\u6765\u4ecb\u7ecd\u9635\u5217\u7684\u4f7f\u7528\u65b9\u6cd5\u5427\u3002<code>[\u503c1, \u503c2, \u503c3]<\/code><\/p>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"%E5%AE%A3%E5%91%8A%E9%98%B5%E5%88%97\"><\/span>\u5ba3\u544a\u9635\u5217<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code><em>\/\/ \u5ba3\u544a\u4e00\u500b\u7a7a\u7684\u9663\u5217<\/em>\n<em>\/\/ \u65b9\u6cd5\u4e00\uff1a\u76f4\u63a5\u5275\u5efa\u4e00\u500b\u7a7a\u9663\u5217 (\u5e38\u898b)<\/em>\nlet array = &#91;];\n\n<em>\/\/ \u65b9\u6cd5\u4e8c\uff1a\u5229\u7528\u5efa\u69cb\u5f0f\u5275\u5efa\u4e00\u500b\u65b0\u9663\u5217<\/em>\nlet array = new Array();\n\n<em>\/\/ \u65b9\u6cd5\u4e09\uff1a\u5ba3\u544a + \u8ce6\u503c\uff0c\u76f4\u63a5\u5275\u5efa\u4e00\u500b\u6709\u503c\u7684\u9663\u5217<\/em>\nlet array = &#91;1, 2, 4];\n<\/code><\/pre>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E4%B8%AD%E6%9F%90%E4%B8%AA%E5%80%BC\"><\/span>\u53d6\u5f97\u9635\u5217\u4e2d\u67d0\u4e2a\u503c<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u73b0\u5728\u6211\u4eec\u6709\u4e00\u4e2a\u5df2\u7ecf\u5ba3\u544a\u5b8c\u6210\u7684\u9635\u5217\uff0c\u82e5\u8981\u5c06\u9635\u5217\u7684\u67d0\u4e2a\u503c\u53d6\u51fa\u6765\u4f7f\u7528\u7684\u8bdd\u8bed\u6cd5\u4e3a \uff0c\u9635\u5217\u7684\u7d22\u5f15\u503c\u4ece\u7b2c\u4e00\u9879\u7531 0 \u5f00\u59cb\uff0c\u5bf9\u5e94\u5982\u4e0b\uff1a<code>\u9663\u5217\u540d\u7a31[\u7d22\u5f15\u503c]<\/code><br><img decoding=\"async\" src=\"https:\/\/www.juejinka.com\/news\/wp-content\/uploads\/2023\/07\/voz3t.jpg\" alt=\"https:\/\/ithelp.ithome.com.tw\/upload\/images\/20230720\/201585099wi6bytNQ4.jpg\"><\/p>\n\n\n\n<p>\u6240\u4ee5\u5728\u4e00\u4e2a\u9635\u5217\u4e2d\uff0c\u5f53\u6211\u4eec\u60f3\u53d6\u51fa\u67d0\u503c\u65f6\u9700\u8981\u5148\u77e5\u9053\u4ed6\u7684\u7d22\u5f15\u503c\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>let array = &#91;\"a\", \"b\", \"c\", \"d\"];\nconsole.log(array&#91;0]); <em>\/\/ \"a\"<\/em>\nconsole.log(array&#91;1]); <em>\/\/ \"b\"<\/em>\nconsole.log(array&#91;2]); <em>\/\/ \"c\"<\/em>\nconsole.log(array&#91;3]); <em>\/\/ \"d\"<\/em>\n<\/code><\/pre>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"Arraylength_%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E9%95%BF%E5%BA%A6\"><\/span>Array.length \u53d6\u5f97\u9635\u5217\u957f\u5ea6<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u5728 JavaScript \u4e2d\u6211\u4eec\u53ef\u4ee5\u7531 Array.length \u53d6\u5f97\u9635\u5217\u7684\u957f\u5ea6\u3002 \u800c\u4f9d\u7167\u903b\u8f91\uff0c\u9635\u5217\u4e2d\u6700\u540e\u4e00\u9879\u7684\u7d22\u5f15\u503c\u4e3a \uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5\u501f\u7531 \u53d6\u5f97\u9635\u5217\u4e2d\u6700\u540e\u4e00\u9879\u7684\u503c\u3002<code>\u9663\u5217\u9577\u5ea6 - 1<\/code><code>array[array.length - 1]<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>let array = &#91;\"a\", \"b\", \"c\", \"d\"];\nconsole.log(array.length); <em>\/\/ \u9663\u5217\u9577\u5ea6<\/em>\nconsole.log(array&#91;0]); <em>\/\/ \u53d6\u5f97\u9663\u5217\u7b2c\u4e00\u9805\u7684\u503c<\/em>\nconsole.log(array&#91;array.length - 1]); <em>\/\/ \u53d6\u5f97\u9663\u5217\u6700\u5f8c\u4e00\u9805\u7684\u503c<\/em>\n<\/code><\/pre>\n\n\n\n<p>\u9664\u6b64\u4e4b\u5916\uff0c\u5c06\u8bbe\u4e3a 0 \u8fd8\u53ef\u4ee5\u76f4\u63a5\u6e05\u7a7a\u6574\u4e2a\u9635\u5217\uff1a<code>Array.length<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>let array = &#91;\"a\", \"b\", \"c\", \"d\"];\nconsole.log(array); <em>\/\/ &#91;'a', 'b', 'c', 'd']<\/em>\narray.length = 0;\nconsole.log(array); <em>\/\/ &#91;] (\u8b8a\u70ba\u7a7a\u9663\u5217)<\/em>\n<\/code><\/pre>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"%E5%8F%96%E5%BE%97%E9%98%B5%E5%88%97%E4%B8%AD%E6%89%80%E6%9C%89%E5%80%BC\"><\/span>\u53d6\u5f97\u9635\u5217\u4e2d\u6240\u6709\u503c<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u73b0\u5728\u6211\u4eec\u77e5\u9053\u5982\u4f55\u53d6\u5f97\u9635\u5217\u4e2d\u67d0\u4e2a\u503c\uff0c\u4e5f\u77e5\u9053\u9635\u5217\u957f\u5ea6\u4e3a\u4f55\uff0c\u8981\u53d6\u51fa\u9635\u5217\u4e2d\u6240\u6709\u503c\u7684\u8bdd\u9700\u8981\u5bf9\u6bcf\u4e2a\u7d22\u5f15\u503c\u4e0b \u76f4\u5230\u6700\u540e\u4e00\u9879\uff0c\u4e5f\u5c31\u662f\u8bf4\u6211\u4eec\u9700\u8981\u4f7f\u7528\u5faa\u73af\u628a\u6574\u4e2a\u9635\u5217\u8dd1\u4e00\u904d\u3002<code>Array[index]<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>let array = &#91;\"a\", \"b\", \"c\", \"d\"];\n<em>\/\/ \u7528 for \u8ff4\u5708\u53d6\u51fa\u6240\u6709\u503c<\/em>\n<em>\/\/ \u9663\u5217\u7d22\u5f15\u503c\u8d77\u59cb\u70ba 0\uff0c\u6240\u4ee5\u5c07\u8b8a\u6578 i \u521d\u59cb\u503c\u8a2d\u70ba 0<\/em>\n<em>\/\/ \u9663\u5217\u6700\u5f8c\u4e00\u9805\u7d22\u5f15\u503c\u70ba array.length - 1\uff0c\u6240\u4ee5\u5c07\u7d50\u675f\u689d\u4ef6\u8a2d\u70ba &lt; array.length<\/em>\nfor (let i = 0; i &lt; array.length; i++) { \n    console.log(array&#91;i]); <em>\/\/ array&#91;\u7d22\u5f15\u503c]<\/em>\n};\n<em>\/\/ \u8f38\u51fa\u503c\u5206\u5225\u70ba \"a\"\u3001\"b\"\u3001\"c\"\u3001\"d\"<\/em>\n<\/code><\/pre>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"ArrayisArray_%E5%88%A4%E6%96%AD%E6%98%AF%E5%90%A6%E4%B8%BA%E9%98%B5%E5%88%97\"><\/span>Array.isArray \u5224\u65ad\u662f\u5426\u4e3a\u9635\u5217<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u5728 JavaScript \u4e2d\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 \u6765\u5224\u65ad\u67d0\u53d8\u91cf\u662f\u5426\u4e3a\u9635\u5217\u578b\u6001\u3002<br><strong>\u8303\u4f8b\uff1a<\/strong><code>Array.isArray(\u8b8a\u6578)<\/code><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>console.log(Array.isArray(1)); <em>\/\/ false<\/em>\nconsole.log(Array.isArray(&#91;])); <em>\/\/ true<\/em>\nconsole.log(Array.isArray(&#91;1])); <em>\/\/ true<\/em>\nlet number = &#91;1, 2, 3];\nconsole.log(Array.isArray(number)); <em>\/\/ true<\/em>\n<\/code><\/pre>\n\n\n\n<h3><span class=\"ez-toc-section\" id=\"%E9%98%B5%E5%88%97%E5%9E%8B%E6%80%81%E8%BD%AC%E6%8D%A2\"><\/span>\u9635\u5217\u578b\u6001\u8f6c\u6362<span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>\u4e0e\u57fa\u672c\u578b\u6001\u53d8\u91cf\u4e00\u6837\uff0c\u9635\u5217\u4e5f\u53ef\u4ee5\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32<\/p>\n\n\n\n<ul>\n<li>toString()<code>let item = [\"a\", \"b\", \"c\", \"d\"]; console.log(item.toString()); <em>\/\/ 'a,b,c,d' (\u5c07\u4e2d\u62ec\u865f\u5167\u7684\u6240\u6709\u503c\u4ee5\u9017\u865f\u9023\u63a5\u8f49\u70ba\u5b57\u4e32\u578b\u614b)<\/em><\/code><\/li>\n\n\n\n<li>String()<code>let item = [\"a\", \"b\", \"c\", \"d\"]; console.log(String(item)); <em>\/\/ 'a,b,c,d'<\/em><\/code><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Array \u9635\u5217 \u5728\u524d\u9762\u4ecb\u7ecd\u53d8\u91cf\u578b\u6001\u65f6\u6211\u4eec\u6709\u63d0\u5230\u9635\u5217\uff0c\u9635\u5217\u662f\u4e00\u4e2a\u6709\u987a\u5e8f\u6027\u7684\u5e8f\u5217\uff0c\u53ef\u4ee5\u50a8\u5b58\u591a\u4e2a\u503c\uff0c\u683c\u5f0f\u4e3a \uff0c\u6bcf\u4e2a\u503c\u7167\u987a\u5e8f\u90fd\u4f1a\u6709\u5bf9\u5e94\u7684\u7d22\u5f15\uff0c\u7d22\u5f15\u4ece 0 \u5f00\u59cb\uff0c\u5ba3\u544a\u540e\u82e5\u8981\u53d6\u503c\u9700\u8981\u900f\u8fc7\u7d22\u5f15&#8230;<\/p>\n","protected":false},"author":6,"featured_media":29319,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"special":[],"_links":{"self":[{"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/posts\/29318"}],"collection":[{"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/comments?post=29318"}],"version-history":[{"count":1,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/posts\/29318\/revisions"}],"predecessor-version":[{"id":29320,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/posts\/29318\/revisions\/29320"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/media\/29319"}],"wp:attachment":[{"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/media?parent=29318"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/categories?post=29318"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/tags?post=29318"},{"taxonomy":"special","embeddable":true,"href":"https:\/\/www.juejinka.com\/news\/wp-json\/wp\/v2\/special?post=29318"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}