\u8fd9\u4e2a\u6709\u70b9\u96be\u61c2\uff0c\u9700\u8981\u4e00\u4e9b\u57fa\u7840\u77e5\u8bc6\u6765\u652f\u6301\u3002<\/p>\n
1\uff0cPromise\u6267\u884c\u7684\u4f18\u5148\u7ea7\u5927\u4e8esetTimeout\/setInterval<\/p>\n
2\uff0casync \u7528\u4e8e\u7533\u660e\u4e00\u4e2a function \u662f\u5f02\u6b65\u7684\uff0c\u6240\u4ee5\u5728\u8be5function\u91cc\u9762\u7684\u7a0b\u5e8f\u90fd\u662f\u5f02\u6b65\u7684\uff0c\u4f46\u6709\u65f6\u4e5f\u9700\u8981\u4f9d\u8d56\u67d0\u4e2a\u51fd\u6570\u6267\u884c\u5b8c\u6210\u5f97\u5230\u7ed3\u679c\u624d\u80fd\u7ee7\u7eed\u6267\u884c \uff0c\u8fd9\u65f6\u5019\u53ef\u4ee5\u5728\u51fd\u6570\u4f53\u91cc\u9762\u4f7f\u7528await<\/p>\n
3\uff0cawait \u53ea\u80fd\u51fa\u73b0\u5728 async \u51fd\u6570\u4e2d<\/p>\n
4\uff0cawait\u540e\u9762\u53ef\u4ee5\u63a5\u7740\u4e00\u4e2a\u76f4\u63a5\u53d8\u91cf\u6216\u8005\u662f\u4e00\u4e2apromise\u5bf9\u8c61<\/p>\n
5\uff0cawait\u540e\u9762\u63a5\u7740\u662fpromise\u5bf9\u8c61\uff0casync\u51fd\u6570\u4f53\u5185\u5c31\u4f1a\u963b\u585e\u8981\u7b49await\u540e\u9762\u7684promise\u51fd\u6570\u6267\u884c\u5b8c\u6210\u624d\u4f1a\u7ee7\u7eed\u5f80\u4e0b\u8d70\u3002async\u51fd\u6570\u4f53\u5916\u7684\u4ee3\u7801\u53ef\u4e0d\u4f1a\u53bb\u4e00
\n\u76f4\u7b49\u5f85\u3002<\/p>\n
6\uff0c\u5982\u679c\u5728\u51fd\u6570\u4e2d return \u4e00\u4e2a\u76f4\u63a5\u91cf\uff0casync \u4f1a\u628a\u8fd9\u4e2a\u76f4\u63a5\u91cf\u901a\u8fc7 Promise.resolve() \u5c01\u88c5\u6210 Promise \u5bf9\u8c61\u3002<\/p>\n
7\uff0c\u5728\u6ca1\u6709 await \u7684\u60c5\u51b5\u4e0b\u6267\u884c async \u51fd\u6570\uff0c\u5b83\u4f1a\u7acb\u5373\u6267\u884c\uff0c\u8fd4\u56de\u4e00\u4e2a Promise \u5bf9\u8c61\uff0c\u5e76\u4e14\uff0c\u7edd\u4e0d\u4f1a\u963b\u585e\u540e\u9762\u7684\u8bed\u53e5\u3002\u8fd9\u548c\u76f4\u63a5new Promise\u5bf9\u8c61\u6548
\n\u679c\u4e00\u6837\u3002<\/p>\n
<\/p>\n
\u7b80\u5355\u6848\u4f8b\uff1a<\/p>\n
setTimeout(function (){\r\n console.log('\u5b9a\u65f6\u5668\u5f00\u59cb\u5566' )\r\n});\r\n\r\nnew Promise (function (resolve){\r\n console.log('\u9a6c\u4e0a\u6267\u884cfor\u5faa\u73af\u5566');\r\n for ( var i = 0 ; i < 10000 ; i++){\r\n i == 99 && resolve();\r\n }\r\n}). then (function(){\r\n console.log( '\u6267\u884cthen\u51fd\u6570\u5566')\r\n});\r\n\r\nconsole.log('\u4ee3\u7801\u6267\u884c\u7ed3\u675f');\r\n\r\n\r\n\u7ed3\u679c\uff1a\r\n\u9a6c\u4e0a\u6267\u884cfor\u5faa\u73af\u5566\r\n\u4ee3\u7801\u6267\u884c\u7ed3\u675f\r\n\u6267\u884cthen\u51fd\u6570\u5566\r\n\u5b9a\u65f6\u5668\u5f00\u59cb\u5566\r\n\r\n<\/pre>\n\u89e3\u91ca\uff1a<\/p>\n
js\u4e3b\u7ebf\u7a0b\u8d70\u5230setTimeout\u65f6\uff0c\u5148\u628asetTimeout\u51fd\u6570\u6254\u8fdbsetTimeout\u961f\u5217\u4e2d\u6682\u65f6\u4e0d\u6267\u884c\u91cc\u9762\u4ee3\u7801\uff0c\u7136\u540ejs\u4e3b\u7ebf\u7a0b\u4ee3\u7801\u53c8\u8d70\u5230new Promise\u5bf9\u8c61\u7acb\u9a6c\u6267\u884c\u91cc\u9762\u7684\u4ee3\u7801\uff0c\u8f93\u51fa\u201c\u9a6c\u4e0a\u6267\u884cfor\u5faa\u73af\u5566\u201d\uff0c\u7531\u4e8enew Promise\u5bf9\u8c61\u8fd4\u56de\u7684\u662f\u00a0Promise\u5bf9\u8c61\u6240\u4ee5\u8981\u6254\u8fdbPromise\u961f\u5217\u4e2d\uff0c\u63a5\u7740js\u4e3b\u7ebf\u7a0b\u63a5\u7740\u5f80\u4e0b\u8d70\uff0c\u8f93\u51fa\u201c\u4ee3\u7801\u6267\u884c\u7ed3\u675f\u201d\uff0c\u4e0b\u9762\u5df2\u7ecf\u6ca1\u4ee3\u7801\u53ef\u4ee5\u6267\u884c\u4e86\uff0cjs\u4e3b\u7ebf\u7a0b\u8fd4\u56de\u67e5\u770b\u662f\u5426\u6709Promise\u961f\u5217\uff0c\u53d1\u73b0\u6709\u4e8e\u662f\u6267\u884c\u4e86\u201c\u6267\u884cthen\u51fd\u6570\u5566\u201d\uff0c\u5269\u4e0b\u5df2\u65e0\u4ee3\u7801\u53ef\u6267\u884c\u5c31\u628a\u5269\u4e0b\u7684setTimeout\u961f\u5217\u91cc\u9762\u7684\u4ee3\u7801\u6267\u884c\u4e86\u8f93\u51fa\u201c\u5b9a\u65f6\u5668\u5f00\u59cb\u5566\u201d<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
\u76f4\u63a5\u6848\u4f8b\uff1a<\/p>\n
function testSometing() {\r\n console.log(\"\u6267\u884ctestSometing\");\r\n return \"testSometing\";\r\n}\r\n\r\nasync function testAsync() {\r\n console.log(\"\u6267\u884ctestAsync\");\r\n return Promise.resolve(\"hello async\");\r\n}\r\n\r\nasync function test() {\r\n console.log(\"test start...\");\r\n const v1 = await testSometing();\/\/\u5173\u952e\u70b91\r\n console.log(v1);\r\n const v2 = await testAsync();\r\n console.log(v2);\r\n console.log(v1, v2);\r\n}\r\n\r\ntest();\r\n\r\nvar promise = new Promise((resolve)=> { console.log(\"promise start..\"); resolve(\"promise\");});\/\/\u5173\u952e\u70b92\r\npromise.then((val)=> console.log(val));\r\n\r\nconsole.log(\"test end...\")\r\n\r\n\u4ee5\u4e0b\u662f\u6267\u884c\u7ed3\u679c\uff1a\r\ntest start...\r\n\u6267\u884ctestSometing\r\npromise start..\r\ntest end...\r\ntestSometing\r\n\u6267\u884ctestAsync\r\npromise\r\nhello async\r\ntestSometing hello async<\/pre>\n <\/p>\n
\u4e0b\u9762\u5f00\u59cb\u89e3\u91ca\uff1a<\/p>\n
js\u4e3b\u7ebf\u7a0b\u5148\u662f\u6267\u884ctest()\u51fd\u6570\u88ab\u8c03\u7528\u4e86\uff0c\u6267\u884c\u4e86\u201ctest start…\u201d\uff0c\u63a5\u7740\u6267\u884c\u4e86testSometing()\u51fd\u6570\u8f93\u51fa\u4e86\u201c\u6267\u884ctestSometing\u201d\uff0c\u7531\u4e8e\u9047\u5230\u4e86await,\u4e3b\u7ebf\u7a0b\u8df3\u51fa\u4e86test\u51fd\u6570\u4f53\u5916\uff0c\u4ee3\u7801\u63a5\u7740\u5f80\u4e0b\u8d70\uff0c\u9047\u5230\u5e76\u6267\u884c\u4e86new Promise\u5bf9\u8c61\uff0c\u8f93\u51fa\u4e86\u201cpromise start..\u201d\uff0c\u5e76\u628anew Promise\u5bf9\u8c61\u63a8\u5165\u5230Promise\u961f\u5217\u4e2d\u3002\u4ee3\u7801\u63a5\u7740\u5f80\u4e0b\u8d70\uff0c\u9047\u5230\u4e86\u201ctest end…\u201d\u3002\u8fd9\u65f6\u5019js\u4e3b\u7ebf\u7a0b\u8d70\u5b8c\uff0c\u5f00\u59cb\u628a\u672a\u6267\u884c\u7684\u652f\u7ebf\u7a0b\u653e\u5165\u5230\u4e3b\u7ebf\u7a0b\u4e2d\u7ee7\u7eed\u6267\u884c\uff0c\u4e8e\u662f\u5c31\u7ee7\u7eed\u8fd4\u56de\u5230\u539f\u6765\u8df3\u51fa\u7684test\u51fd\u6570\u4e2d\u90a3\u5730\u65b9\u7ee7\u7eed\u8dd1\u4ee3\u7801\uff0c\u6267\u884c\u5230console.log(v1)\u8f93\u51fa\u201ctestSometing\u201d\uff0c\u63a5\u7740\u8d70\u5230\u5e76\u6267\u884ctestAsync\u51fd\u6570\u8f93\u51fa\u201c\u6267\u884ctestAsync\u201d\uff0c\u7531\u4e8e\u9047\u5230\u4e86await,\u4e3b\u7ebf\u7a0b\u518d\u6b21\u8df3\u51fa\u4e86test\u51fd\u6570\u4f53\u5916\uff0c\u4ee3\u7801\u63a5\u7740\u5f80\u4e0b\u8d70\uff0c\u53d1\u73b0\u5df2\u7ecf\u6ca1\u4ec0\u4e48\u4ee3\u7801\u53ef\u4ee5\u8fd0\u884c\u4e86\uff0c\u5c31\u628a\u5269\u4e0b\u7684new Promise\u5bf9\u8c61\u7684then\u56de\u8c03\u6267\u884c\u4e86\uff0c\u8f93\u51fa\u201cpromise\u201d\uff0c\u63a5\u7740\u56detest()\u51fd\u6570\u4f53\u5185\uff0c\u7531\u4e8etestAsync()\u662fnew Promise\u5bf9\u8c61\uff0c\u8fd8\u8981\u518d\u8df3\u51fatest\u51fd\u6570\uff0c\u7ee7\u7eed\u5f80\u4e0b\u8d70\u4f9d\u7136\u6ca1\u4efb\u4f55\u4ee3\u7801\u53ef\u4ee5\u6267\u884c\u4e86\u3002\u8fd4\u56detest\u51fd\u6570\u4f53\u5185\uff0c\u6267\u884ctestAsync()\u7684\u8fd4\u56de\u7684\u503c\uff0cconsole.log(v2)\u8f93\u51fa\u201chello async\u201d\uff0c\u540e\u9762\u8f93\u51fa\u201ctestSometing hello async\u201d\u3002<\/p>\n
<\/p>\n
\u91cd\u70b9\u6ce8\u610f\uff1a
\n1\uff0c\u5728async\u51fd\u6570\u4e2d\uff0c\u9047\u5230await\u540e\u9762\u63a5\u7740\u662f\u666e\u901a\u51fd\u6570\u65f6\uff0c\u5148\u628a\u666e\u901a\u51fd\u6570\u91cc\u9762\u7684\u4ee3\u7801\u6267\u884c\u4e86\u540e\uff0c\u5c31\u4f1a\u8df3\u51faasync\u51fd\u6570\u4f53\u5916\uff0c\u4ee3\u7801\u63a5\u7740\u5f80\u4e0b\u8dd1\uff0c\u76f4\u5230\u8dd1\u5b8c
\n\u4e86\u540e\u5728\u91cd\u65b0\u56de\u5230await\u521a\u521a\u8df3\u51fa\u7684\u4f4d\u7f6e\uff0c\u7ee7\u7eed\u8dd1async\u51fd\u6570\u4f53\u5185\u7684\u4ee3\u7801\u3002<\/p>\n
2\uff0c\u5728async\u51fd\u6570\u4e2d\uff0c\u9047\u5230await\u540e\u9762\u63a5\u7740\u4e5f\u662fasync\u51fd\u6570\u65f6\u4e5f\u5c31\u662fPromise\u5bf9\u8c61\uff0c\u4e5f\u4f1a\u5148\u6267\u884cawait\u7d27\u63a5\u7684\u51fd\u6570\u4ee3\u7801\uff0c\u4e4b\u540e\u8df3\u51faasync\u51fd\u6570\u4f53\u5916\uff0c\u4ee3\u7801
\n\u63a5\u7740\u5f80\u4e0b\u8dd1\uff0c\u76f4\u5230\u8dd1\u5b8c\u4e86\u540e\u5728\u91cd\u65b0\u56de\u5230await\u521a\u521a\u8df3\u51fa\u7684\u4f4d\u7f6e\uff0c\u7531\u4e8eawait\u540e\u9762\u63a5\u7740\u662fPromise\u5bf9\u8c61\uff0c\u518d\u6b21\u8df3\u51faasync\u51fd\u6570\u4f53\u5916\u3002\u7ee7\u7eed\u8dd1\u4e0b\u9762\u7684\u4ee3\u7801\u3002
\n\u76f4\u5230\u8dd1\u5b8c\u540e\u624d\u518d\u6b21\u8fd4\u56de\u5230await\u4ee3\u7801\u5904\u3002<\/p>\n
<\/p>\n
<\/p>\n
\u5728\u6765\u4e00\u4e2a\u6848\u4f8b\uff0c\u8fd9\u6b21\u52a0\u5165setTimeout<\/p>\n
async function async1() {\r\n console.log( 'async1 start' )\r\n await async2()\r\n console.log( 'async1 end' )\r\n}\r\n\r\nasync function async2() {\r\n console.log( 'async2' )\r\n}\r\n\r\nconsole.log( 'script start' )\r\n\r\nsetTimeout( function () {\r\n console.log( 'setTimeout' )\r\n}, 0 )\r\n\r\nasync1();\r\n\r\nnew Promise( function ( resolve ) {\r\n console.log( 'promise1' )\r\nresolve();\r\n} ).then( function () {\r\n console.log( 'promise2' )\r\n} )\r\n\r\nconsole.log( 'script end' )<\/pre>\n <\/p>\n
<\/p>\n
\u7ed3\u679c\uff1a<\/p>\n
script start\r\nasync1 start\r\nasync2\r\npromise1\r\nscript end\r\npromise2\r\nasync1 end\r\nsetTimeout<\/pre>\n <\/p>\n
\u8fc7\u7a0b\uff1a<\/p>\n
js\u4e3b\u7ebf\u7a0b\u8d70\u5230\u5e76\u8f93\u51fa\u201cscript start\u201d\uff0c\u7531\u4e8esetTimeout\u6267\u884c\u7684\u4f18\u5148\u7ea7\u4f4e\u4e8e\u4e3b\u7ebf\u7a0b\u4e0a\u7684\u4efb\u52a1\u548cPromise\u4e0a\u7684\u4efb\u52a1\u6240\u4ee5\u8981\u7b49\u5230\u6700\u540e\uff0c\u76f4\u5230\u6267\u884c
\nasync1()\u51fd\u6570\u5185\uff0c\u8f93\u51fa\u201casync1 start\u201d\uff0c\u5728\u6267\u884casync2()\u51fd\u6570\u8f93\u51fa\u201casync2\u201d\uff0c\u7531\u4e8e\u8d70\u5230async2()\u51fd\u6570\u65f6\u9047\u5230await\uff0c\u8981\u8df3\u51faasync1()\u51fd
\n\u6570\u4f53\u5916\uff0c\u63a5\u7740\u4ee3\u7801\u5f80\u4e0b\u8dd1\uff0c\u6267\u884cnew Promise\u5bf9\u8c61\uff0c\u8f93\u51fa\u201cpromise1\u201d\uff0cnew Promise\u5bf9\u8c61\u8fdb\u5165\u5230Promise\u961f\u5217\u4e2d\uff0c\u7ee7\u7eed\u5f80\u4e0b\u8d70\uff0c\u8f93
\n\u51fa\u201cscript end\u201d\uff0c\u73b0\u5728\u56de\u5230async1()\u51fd\u6570\u4f53\u5185\u4e2d\u7684await async2()\u5904\uff0c\u7531\u4e8eawait\u540e\u9762\u63a5\u7740async2()\u8fd4\u56de\u7684\u662fPromise\u5bf9\u8c61\u8fd8\u8981\u518d\u6b21\u8df3\u51fa
\nasync1()\u51fd\u6570\u4f53\u5916\u7ee7\u7eed\u6267\u884c\u4ee5\u5916\u7684\u4ee3\u7801\uff0c\u8fd9\u65f6\u5019\u6b63\u597d\u6709Promise\u961f\u5217\u4e2d\u7684then\u9700\u8981\u6267\u884c\uff0c\u4e8e\u662f\u8f93\u51fa\u201cpromise2\u201d\uff0c\u5269\u4e0b\u6ca1\u4ee3\u7801\u53ef\u4ee5\u8dd1\u4e86\uff0c
\nsetTimeout\u4ecd\u7136\u9760\u540e\u4f18\u5148\u7ea7\u4f4e\uff0c\u518d\u6b21\u56de\u5230async1()\u51fd\u6570\u4f53\u5185\uff0c\u63a5\u7740\u6267\u884c\u8f93\u51fa\u201casync1 end\u201d\uff0c\u6700\u540e\u5269\u4e0b\u4e3b\u7ebf\u7a0b\u548cPromise\u961f\u5217\u7684\u4efb\u52a1\u90fd\u6267\u884c
\n\u5b8c\u6210\u4e86\uff0c\u5c31\u8f93\u51fa\u201csetTimeout\u201d<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
\u8fd9\u4e2a\u6709\u70b9\u96be\u61c2\uff0c\u9700\u8981\u4e00\u4e9b\u57fa\u7840\u77e5\u8bc6\u6765\u652f\u6301\u3002 1\uff0cPromise\u6267\u884c\u7684\u4f18\u5148\u7ea7\u5927\u4e8esetTimeout\/setInte […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-7151","post","type-post","status-publish","format-standard","hentry","category-11"],"_links":{"self":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/7151","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7151"}],"version-history":[{"count":0,"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/7151\/revisions"}],"wp:attachment":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7151"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7151"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7151"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}