{"id":1048,"date":"2022-04-19T11:44:37","date_gmt":"2022-04-19T03:44:37","guid":{"rendered":"http:\/\/zhuxinyong.com\/?p=1048"},"modified":"2023-02-16T14:40:23","modified_gmt":"2023-02-16T06:40:23","slug":"8-array-de-shi-li-fang-fa-yi","status":"publish","type":"post","link":"https:\/\/zhuxinyong.com\/?p=1048","title":{"rendered":"8 – Array \u7684\u5b9e\u4f8b\u65b9\u6cd5\u4e00"},"content":{"rendered":"

\"\"<\/p>\n

\u539f\u6587\u5730\u5740\uff1ahttps:\/\/dev.to\/bhagatparwinder\/array-instance-methods-59a2<\/a><\/p>\n

Array \u7684\u5b9e\u4f8b\u65b9\u6cd5\u5b58\u5728\u4e8e prototype \u4e0a\u3002<\/p>\n

<\/span><\/a>concat<\/h3>\n

\u8fd4\u56de\u6570\u7ec4\u548c\u53e6\u4e00\u6570\u7ec4\u6216\u503c\u8fde\u63a5\u8fd4\u56de\u7684\u65b0\u6570\u7ec4\u3002<\/p>\n

const array1 = ["a", "b", "c"];\nconst array2 = ["d", "e", "f"];\nconst array3 = array1.concat(array2);\n\nconsole.log(array3); \/\/ ["a", "b", "c", "d", "e", "f"]\n<\/code><\/pre>\n
\u4f60\u4e5f\u53ef\u4ee5\u4f7f\u7528\u6570\u7ec4\u8fde\u63a5\u4e00\u4e2a\u503c\uff1a<\/p>\n
const letters = ["a", "b", "c"];\nconst alphaNumeric = letters.concat(1, [2, 3]);\nconsole.log(alphaNumeric); \/\/ ["a", "b", "c", 1, 2, 3]\n<\/code><\/pre>\n
\u4e5f\u53ef\u4ee5\u8fde\u63a5\u4e00\u4e2a\u5d4c\u5957\u7684\u6570\u7ec4\uff1a<\/p>\n
const num1 = [[1]];\nconst num2 = [2, [3]];\nconst numbers = num1.concat(num2);\n\nconsole.log(numbers); \/\/ [[1], 2, [3]]\n\n\/\/ modify the first element of num1\nnum1[0].push(4);\nconsole.log(numbers); \/\/ [[1, 4], 2, [3]]\n<\/code><\/pre>\n
<\/span><\/a>entries<\/h3>\n
\u4f7f\u7528\u5bf9\u8c61\u4e0a\u7684 entries<\/strong>\u3001keys<\/strong>\u3001values<\/strong> \u65b9\u6cd5\u5f88\u5e38\u89c1\uff0c\u4f46\u662f\u6570\u7ec4\u4e5f\u652f\u6301\u5b83\u4eec\u3002<\/p>\n
entries \u65b9\u6cd5\u8fd4\u56de key\/value \u7684 iterator<\/strong> \u3002<\/p>\n
const array1 = ["a", "b", "c"];\nconst iterator = array1.entries();\n\nconsole.log(iterator.next().value); \/\/ [0, "a"]\nconsole.log(iterator.next().value); \/\/ [1, "b"]\n<\/code><\/pre>\n
<\/span><\/a>keys<\/h3>\n
keys \u8fd4\u56de iterator \u7684\u952e\u3002<\/p>\n
const array1 = ["a", "b", "c"];\nconst iterator = array1.keys();\n\nconsole.log(iterator.next().value); \/\/ 0\nconsole.log(iterator.next().value); \/\/ 1\nconsole.log(iterator.next().value); \/\/ 2\n<\/code><\/pre>\n
<\/span><\/a>values<\/h3>\n
values \u8fd4\u56de iterator \u7684\u503c\u3002<\/p>\n
const array2 = ["a", "b", "c"];\nconst i = array2.values();\n\nconsole.log(i.next().value); \/\/ a\nconsole.log(i.next().value); \/\/ b\nconsole.log(i.next().value); \/\/ c\n<\/code><\/pre>\n
<\/span><\/a>includes<\/h3>\n
includes \u65b9\u6cd5\u5224\u65ad\u6570\u7ec4\u662f\u5426\u5305\u542b\u4e00\u4e2a\u6307\u5b9a\u7684\u5143\u7d20\uff0c\u6839\u636e\u7ed3\u679c\u8fd4\u56de true \u548c false\u3002<\/p>\n
const array1 = [1, 2, 3];\nconsole.log(array1.includes(3)); \/\/ true\nconsole.log(array1.includes(4)); \/\/ false\n\nconst pets = ["cat", "dog", "bat"];\nconsole.log(pets.includes("cat")); \/\/ true\nconsole.log(pets.includes("at")); \/\/ false\n<\/code><\/pre>\n
includes \u65b9\u6cd5\u8fd8\u5305\u542b\u7b2c\u4e8c\u4e2a\u53c2\u6570\uff1aindex\uff0c\u6b64\u53c2\u6570\u4f7f\u5f97 includes \u65b9\u6cd5\u68c0\u6d4b\u7ed9\u5b9a\u503c\u7684\u4e0b\u6807\u662f\u5426\u5927\u4e8e\u6216\u7b49\u4e8e\u7ed9\u5b9a\u7684\u4e0b\u6807\u3002<\/p>\n
let example = ["a", "b", "c"]\n\nexample.includes("b", 3); \/\/ false\nexample.includes("b", 100); \/\/ false\nexample.includes("b", 1); \/\/ true\n<\/code><\/pre>\n
<\/span><\/a>indexOf<\/h3>\n
indexOf \u8fd4\u56de\u6570\u7ec4\u4e2d\u7ed9\u5b9a\u5143\u7d20\u7684\u4e0b\u6807\uff0c\u82e5\u4e0d\u5b58\u5728\u8fd4\u56de -1 \u3002ES6 \u4e4b\u524d\u7528\u6765\u68c0\u6d4b\u6570\u7ec4\u4e2d\u662f\u5426\u5b58\u5728\u67d0\u4e2a\u503c\uff0c\u6ca1\u6709\u7279\u6b8a\u9700\u6c42\u73b0\u5728\u4e00\u822c\u4f7f\u7528 includes \u65b9\u6cd5\uff0c\u9664\u975e\u4f60\u60f3\u77e5\u9053\u67d0\u4e2a\u5143\u7d20\u7684\u4e0b\u6807\u3002<\/p>\n
var array = [2, 9, 9];\narray.indexOf(2); \/\/ 0\narray.indexOf(7); \/\/ -1\narray.indexOf(9, 2); \/\/ 2\narray.indexOf(2, -1); \/\/ -1\narray.indexOf(2, -3); \/\/ 0\n<\/code><\/pre>\n
<\/span><\/a>findIndex<\/h3>\n
\u5230\u8fd9\u91cc\uff0c\u4f60\u5df2\u7ecf\u5b66\u5230\u4e86 indexOf \u548c includes \u6765\u5bfb\u627e\u4e00\u4e2a\u5143\u7d20\u6216\u4e0b\u6807\uff0cfindIndex \u65b9\u6cd5\u7c7b\u4f3c\u3002\u5b83\u8fd4\u56de\u7b2c\u4e00\u4e2a\u6ee1\u8db3\u56de\u8c03\u51fd\u6570\u6216\u68c0\u6d4b\u51fd\u6570\u7684\u5143\u7d20\u4e0b\u6807\u3002<\/p>\n
\u6211\u5efa\u8bae indexOf \u7528\u5728\u539f\u59cb\u6570\u636e\u7c7b\u578b\u4e0a\uff1astrings\u3001numbers \u6216\u8005 booleans\uff0c\u800c findIndex \u5219\u7528\u5728\u975e\u539f\u59cb\u7c7b\u578b\u4e0a\uff1aobjects\u3002<\/p>\n
const fruits = ["apple", "banana", "cantaloupe", "blueberries", "grapefruit"];\nconst index = fruits.findIndex(fruit => fruit === "blueberries");\n\nconsole.log(index); \/\/ 3\nconsole.log(fruits[index]); \/\/ blueberries\n<\/code><\/pre>\n
<\/span><\/a>find<\/h3>\n
find \u65b9\u6cd5\u8fd4\u56de\u6570\u7ec4\u4e2d\u7b2c\u4e00\u4e2a\u6ee1\u8db3\u6761\u4ef6\u7684\u503c\uff0c find \u8fd4\u56de\u7684\u662f\u503c\u800c findIndex \u8fd4\u56de\u7684\u662f\u4e0b\u6807\u3002<\/p>\n
const array = [7, 33, 47, 99, 2, 103, 79];\nconst found = array.find(element => element > 10);\nconsole.log(found); \/\/ 33\n<\/code><\/pre>\n
<\/span><\/a>join<\/h3>\n
join \u65b9\u6cd5\u662f\u4e00\u4e2a\u4f7f\u7528\u9891\u7387\u5f88\u9ad8\u7684\u65b9\u6cd5\uff0c\u5b83\u8fd4\u56de\u4e00\u4e2a\u6570\u7ec4\u4e2d\u6240\u6709\u7684\u5143\u7d20\u8fde\u63a5\u6210\u7684\u5b57\u7b26\u4e32\u3002\u4f60\u53ef\u4ee5\u4f7f\u7528\u4e00\u4e2a\u7279\u5b9a\u7684\u5206\u9694\u7b26\u6765\u8fde\u63a5\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u5206\u9694\u7b26\u662f ,<\/strong>\u3002<\/p>\n
const fruits = ["Apple", "Banana", "Raspberry"];\n\nconsole.log(fruits.join()); \/\/ Apple,Banana,Raspberry\nconsole.log(fruits.join("")); \/\/ AppleBananaRaspberry\nconsole.log(fruits.join("|")); \/\/ Apple|Banana|Raspberry\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u539f\u6587\u5730\u5740\uff1ahttps:\/\/dev.to\/bhagatparwinder\/array-instance...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[249,2,20,3],"tags":[96,6],"class_list":["post-1048","post","type-post","status-publish","format-standard","hentry","category-javascript","category-all","category-frontend","category-tech","tag-array","tag-javascript"],"_links":{"self":[{"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/posts\/1048","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1048"}],"version-history":[{"count":3,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/posts\/1048\/revisions"}],"predecessor-version":[{"id":1051,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=\/wp\/v2\/posts\/1048\/revisions\/1051"}],"wp:attachment":[{"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1048"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1048"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zhuxinyong.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1048"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}