{"id":675,"date":"2019-04-17T11:13:50","date_gmt":"2019-04-17T03:13:50","guid":{"rendered":"https:\/\/wyxxt.org.cn\/?p=675"},"modified":"2023-12-04T16:49:15","modified_gmt":"2023-12-04T08:49:15","slug":"js%e6%95%b0%e7%bb%84%e6%93%8d%e4%bd%9c","status":"publish","type":"post","link":"https:\/\/wyxxt.org.cn\/?p=675","title":{"rendered":"js\u6570\u7ec4\u64cd\u4f5c"},"content":{"rendered":"

\u5224\u65ad\u6570\u7ec4\u4e3a\u7a7a<\/h3>\n
const arr = [];\nif(arr.length === 0) {\n    console.log('arr\u4e3a\u7a7a')\n}\n<\/code><\/pre>\n
\u5224\u65ad\u6570\u7ec4\u662f\u5426\u5305\u542b\u67d0\u4e2a\u503c<\/h3>\n
    \n
  1. arr.indexOf()<\/li>\n<\/ol>\n
    if(arr.indexOf(2) !== -1) {\n    console.log('\u6570\u7ec4\u542b\u67092');\n}else{\n    console.log('\u6570\u7ec4\u4e0d\u542b2');\n}\n<\/code><\/pre>\n
      \n
    1. arr.includes() ES6\u65b0\u65b9\u6cd5<\/li>\n<\/ol>\n
      const arr = [1, 2, 3, 4];\nif(arr.includes(2)) {\n    console.log('\u6570\u7ec4\u4e2d\u67092');\n}else{\n    console.log('\u6570\u7ec4\u4e2d\u65e02');\n}\n<\/code><\/pre>\n
      \u6570\u7ec4\u8f6c\u5b57\u7b26\u4e32<\/h3>\n
      const arr = ['hello', 'world', '!'];\nconst str = arr.join(' '); \/\/hello world !\n<\/code><\/pre>\n
      \u5b57\u7b26\u4e32\u8f6c\u6570\u7ec4<\/h4>\n
      const str = 'hello,world,!';\nconst arr = str.split(','); \/\/helloworld!\n<\/code><\/pre>\n
      \u6570\u7ec4\u5143\u7d20\u98a0\u5012\u987a\u5e8f<\/h3>\n
      const arr1 = ['hello','world','!'];\nconst arr2 = arr1.reverse(); \/\/['!', 'world', 'hello']\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
      \u5224\u65ad\u6570\u7ec4\u4e3a\u7a7a const arr = []; if(arr.length === 0) { console.l […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[15],"tags":[411],"class_list":["post-675","post","type-post","status-publish","format-standard","hentry","category-15","tag-js"],"_links":{"self":[{"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/675","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=675"}],"version-history":[{"count":4,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/675\/revisions"}],"predecessor-version":[{"id":761,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/675\/revisions\/761"}],"wp:attachment":[{"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=675"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=675"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wyxxt.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=675"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}