{"id":6486,"date":"2022-10-12T13:15:16","date_gmt":"2022-10-12T05:15:16","guid":{"rendered":"https:\/\/www.lilichao.com\/?p=6486"},"modified":"2022-10-12T13:15:16","modified_gmt":"2022-10-12T05:15:16","slug":"%e5%ae%8f%e4%bb%bb%e5%8a%a1%e5%92%8c%e5%be%ae%e4%bb%bb%e5%8a%a1","status":"publish","type":"post","link":"https:\/\/lilichao.com\/?p=6486","title":{"rendered":"\u5b8f\u4efb\u52a1\u548c\u5fae\u4efb\u52a1"},"content":{"rendered":"\n<p>\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u6bb5\u4ee3\u7801\uff0c\u4f60\u80fd\u8bf4\u51fa\u5b83\u5728\u63a7\u5236\u53f0\u4e2d\u7684\u8f93\u51fa\u7ed3\u679c\u5417\uff1f<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-js\" data-lang=\"JavaScript\"><code>console.log(1)\n\nPromise.resolve().then(() =&gt; {\n    console.log(2)\n})\n\nconsole.log(3)<\/code><\/pre><\/div>\n\n\n\n<p>\u8981\u771f\u6b63\u7684\u7406\u89e3\u8fd9\u4e00\u6bb5\u4ee3\u7801\uff0c\u6211\u4eec\u5fc5\u987b\u8981\u5148\u641e\u61c2Promise\u4e2d\u7684\u5b9e\u4f8b\u65b9\u6cd5then\u5230\u5e95\u662f\u5728\u505a\u4ec0\u4e48\uff1f\u4e4b\u524d\u5728\u5b66\u4e60Promise\u65f6\uff0c\u6211\u4eec\u5c31\u5df2\u7ecf\u8bf4\u8fc7\u4e86\uff0cthen\u76f8\u5f53\u4e8e\u4e3aPromise\u8bbe\u7f6e\u4e86\u4e00\u4e2a\u56de\u8c03\u51fd\u6570\uff0c\u5f53Promise\u4e2d\u7684\u6570\u636e\u5904\u7406\u5b8c\u6bd5\u65f6\uff0c\u4fbf\u4f1a\u8c03\u7528then\u6240\u8bbe\u7f6e\u7684\u56de\u8c03\u51fd\u6570\u6765\u7ee7\u7eed\u540e\u7eed\u4efb\u52a1\u3002<\/p>\n\n\n\n<p>\u4e0a\u4f8b\u4e2d\uff0c\u6211\u4eec\u901a\u8fc7Promise.resolve()\u521b\u5efa\u4e86\u4e00\u4e2a\u7406\u89e3\u5b8c\u6210\u7684Promise\uff0c\u90a3\u4e48\u6309\u9053\u7406\u8bb2then\u4e2d\u7684\u56de\u8c03\u51fd\u6570\u5e94\u8be5\u7acb\u523b\u6267\u884c\u554a\uff1f\u56e0\u4e3aPromise\u5df2\u7ecf\u5b8c\u6210\u4e86\u554a\uff1f\u6240\u4ee5\u6253\u5370\u7684\u987a\u5e8f\u4e0d\u5e94\u8be5\u662f\u201c1 2 3\u201d\u5417\uff1f\u5982\u679c\u80fd\u60f3\u5230\u8fd9\u4e9b\u90a3\u4e48\u8bc1\u660e\u4e4b\u524d\u8bb2\u89e3\u7684Promise\u4f60\u5df2\u7ecf\u7406\u89e3\u7684\u5dee\u4e0d\u591a\u4e86\uff0c\u4f46\u662f\u8fd8\u4e0d\u591f\u51c6\u786e\uff01<\/p>\n\n\n\n<p>then\u4e2d\u7684\u56de\u8c03\u51fd\u6570\u4f1a\u5728Promise\u5b8c\u6210\u540e\u88ab\u8c03\u7528\uff0c\u4f46\u662f\u6ce8\u610f\u5e76\u4e0d\u662f\u7acb\u523b\u5c31\u8c03\u7528\uff0c\u800c\u662f\u91c7\u7528\u4e00\u79cd\u548c\u5b9a\u65f6\u5668\u7c7b\u4f3c\u7684\u5904\u7406\u65b9\u5f0f\uff0c\u8bb2\u51fd\u6570\u653e\u5165\u5230\u4e00\u4e2a\u4efb\u52a1\u961f\u5217\u4e2d\uff0c\u800c\u961f\u5217\u4e2d\u7684\u4ee3\u7801\u4f1a\u5728\u8c03\u7528\u6808\u4e2d\u7684\u4ee3\u7801\u6267\u884c\u5b8c\u6bd5\u540e\u624d\u4f1a\u6267\u884c\u3002\u4e5f\u5c31\u662f\u8bf4then\u4e2d\u7684\u4ee3\u7801\u603b\u662f\u5728\u5f53\u524d\u8c03\u7528\u6808\u4e2d\u7684\u4ee3\u7801\u6267\u884c\u5b8c\u540e\u624d\u6267\u884c\u3002\u6240\u4ee5\u4e0a\u8fb9\u4ee3\u7801\u7684\u8f93\u51fa\u7ed3\u679c\u5e94\u8be5\u4e3a\uff1a\u201c1 3 2\u201d<\/p>\n\n\n\n<p>\u90a3\u4e48\u95ee\u9898\u53c8\u6765\u4e86\uff0c\u5982\u679c\u662f\u8fd9\u6837\u7684\u4ee3\u7801\u5462\uff1f<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-js\" data-lang=\"JavaScript\"><code>setTimeout(()=&gt;{\n    console.log(1)\n})\n\nPromise.resolve().then(() =&gt; {\n    console.log(2)\n})<\/code><\/pre><\/div>\n\n\n\n<p>\u9519\u8bef\u7684\u5206\u6790\uff1asetTimeout\u662f\u5b9a\u65f6\u5668\uff0c\u5b83\u4f1a\u5728\u4e00\u6bb5\u65f6\u95f4\u540e\u5c06\u51fd\u6570\u653e\u5165\u5230\u4efb\u52a1\u961f\u5217\u4e2d\uff0c\u800c\u6211\u4eec\u6ca1\u6709\u6307\u5b9a\u65f6\u95f4\uff0c\u4e5f\u5c31\u610f\u5473\u7740\u51fd\u6570\u4f1a\u7acb\u523b\u653e\u5165\u5230\u4efb\u52a1\u961f\u5217\u4e2d\u3002then\u540c\u6837\u4e5f\u662f\u5c06\u51fd\u6570\u653e\u5165\u5230\u4efb\u52a1\u961f\u5217\u4e2d\uff0c\u5e76\u4e14\u8fd9\u4e2aPromise\u662f\u4e00\u4e2a\u7acb\u5373\u5b8c\u6210\u7684Promise\u6240\u4ee5\u51fd\u6570\u4e5f\u662f\u7acb\u523b\u8fdb\u5165\u4efb\u52a1\u961f\u5217\u3002\u90a3\u4e48\u6309\u7167\u6267\u884c\u987a\u5e8f\u6765\u8bb2\uff0c\u5b9a\u65f6\u5668\u5728\u524d\uff0cthen\u5728\u540e\uff0c\u6240\u4ee5\u5b9a\u65f6\u5668\u4e2d\u7684\u51fd\u6570\u5e94\u8be5\u5148\u8fdb\u5165\u961f\u5217\uff0c\u961f\u5217\u53c8\u662f\u5148\u8fdb\u5148\u51fa\u7684\uff0c\u6240\u4ee5\u5e94\u8be5\u51481\u540e2\u3002<\/p>\n\n\n\n<p>\u4e0a\u8fb9\u7684\u5206\u6790\u770b\u4f3c\u5408\u7406\uff0c\u5b9e\u9645\u4e0a\u662f\u4e0d\u5bf9\u7684\u3002\u56e0\u4e3asetTimeout\u548cthen\u867d\u7136\u90fd\u5c06\u51fd\u6570\u653e\u5165\u5230\u961f\u5217\u4e2d\uff0c\u4f46\u662f\u5374\u4e0d\u662f\u540c\u4e00\u4e2a\u961f\u5217\u3002\u4e3a\u4e86\u66f4\u5408\u7406\u7684\u5904\u7406\u5f02\u6b65\u4efb\u52a1\uff0cES\u6807\u51c6\u89c4\u5b9a\u4e86\u4e00\u4e2a\u5185\u90e8\u7684\u961f\u5217\u201cPromiseJobs\u201d\uff0c\u8fd9\u4e2a\u961f\u5217\u662f\u4e13\u95e8\u7528\u6765\u653e\u7f6e\u7531Promise\u4ea7\u751f\u7684\u56de\u8c03\u51fd\u6570\u7684\uff08then\u3001catch\u3001finally\uff09\uff0c\u8fd9\u4e2a\u961f\u5217\u6211\u4eec\u901a\u5e38\u88ab\u79f0\u4e3a\u201c\u5fae\u4efb\u52a1\u961f\u5217\uff08microtask queue\uff09\u201d\u3002\u76f8\u5bf9\u7684\uff0csetTimeout\u8fd9\u4e9b\u65b9\u6cd5\u662f\u5c06\u51fd\u6570\u653e\u5165\u5230\u4e86\u201c\u5b8f\u4efb\u52a1\u961f\u5217\uff08macrotask queue\uff09\u201d\u3002<\/p>\n\n\n\n<p>\u7b80\u5355\u6765\u8bf4\uff0c\u4efb\u52a1\u961f\u5217\u6709\u4e24\u4e2a\uff0c\u5b8f\u4efb\u52a1\u961f\u5217\u548c\u5fae\u4efb\u52a1\u961f\u5217\u3002\u4ee3\u7801\u6267\u884c\u65f6\uff0c\u5b8f\u4efb\u52a1\u8fdb\u5165\u5230\u5b8f\u4efb\u52a1\u961f\u5217\uff0c\u5fae\u4efb\u52a1\u8fdb\u5165\u5230\u5fae\u4efb\u52a1\u961f\u5217\u3002\u90a3\u4e48\u54ea\u4e9b\u4efb\u52a1\u65f6\u5fae\u4efb\u52a1\uff0c\u54ea\u4e9b\u4efb\u52a1\u662f\u5b8f\u4efb\u52a1\u5462\uff1f\u5176\u5b9e\u5927\u90e8\u5206\u7684\u4efb\u52a1\u90fd\u5c5e\u4e8e\u5b8f\u4efb\u52a1\u3002\u800c\u5fae\u4efb\u52a1\u901a\u5e38\u5728\u4ee3\u7801\u8fd0\u884c\u65f6\u4ea7\u751f\uff0c\u901a\u5e38\u662f\u7531Promise\u6240\u521b\u5efa\u7684\uff0cPromise\u7684then\u3001catch\u3001finally\u4e2d\u7684\u56de\u8c03\u51fd\u6570\u4f1a\u4f5c\u4e3a\u5fae\u4efb\u52a1\u8fdb\u5165\u5230\u5fae\u4efb\u52a1\u961f\u5217\u4e2d\u3002<\/p>\n\n\n\n<p>JS\u4ee3\u7801\u6267\u884c\u65f6\uff0c\u6bcf\u4e00\u4e2a\u5b8f\u4efb\u52a1\u6267\u884c\u5b8c\u6bd5\u540e\uff0cJS\u5f15\u64ce\u4f1a\u7acb\u5373\u6267\u884c\u5fae\u4efb\u52a1\u961f\u5217\u4e2d\u7684\u6240\u6709\u4efb\u52a1\uff0c\u7136\u540e\u624d\u662f\u6267\u884c\u5b8f\u4efb\u52a1\u961f\u5217\u4e2d\u7684\u4efb\u52a1\u3002\u6362\u53e5\u8bdd\u4e2dthen\u4e2d\u7684\u56de\u8c03\u51fd\u6570\uff08\u5fae\u4efb\u52a1\uff09\u4f1a\u5148\u4e8e\u5b9a\u65f6\u5668\u4e2d\u7684\u56de\u8c03\u51fd\u6570\uff08\u5b8f\u4efb\u52a1\uff09\u6267\u884c\u3002\u6240\u4ee5\u4e0a\u4f8b\u4e2d\u4ee3\u7801\u7684\u6267\u884c\u7ed3\u679c\u5e94\u8be5\u4e3a\uff1a\u201c2 1\u201d\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u4e0a\u8fb9\u7684\u5185\u5bb9\u4f60\u7406\u89e3\u4e86\uff0c\u53ef\u4ee5\u5c1d\u8bd5\u5206\u6790\u4e00\u4e0b\u8fd9\u6bb5\u4ee3\u7801\uff1a<\/p>\n\n\n\n<div class=\"hcb_wrap\"><pre class=\"prism line-numbers lang-js\" data-lang=\"JavaScript\"><code>console.log(1);\n\nsetTimeout(() =&gt; console.log(2));\n\nPromise.resolve().then(() =&gt; console.log(3));\n\nPromise.resolve().then(() =&gt; setTimeout(() =&gt; console.log(4)));\n\nPromise.resolve().then(() =&gt; console.log(5));\n\nsetTimeout(() =&gt; console.log(6));\n\nconsole.log(7);<\/code><\/pre><\/div>\n","protected":false},"excerpt":{"rendered":"<p>\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u6bb5\u4ee3\u7801\uff0c\u4f60\u80fd\u8bf4\u51fa\u5b83\u5728\u63a7\u5236\u53f0\u4e2d\u7684\u8f93\u51fa\u7ed3\u679c\u5417\uff1f \u8981\u771f\u6b63\u7684\u7406\u89e3\u8fd9\u4e00\u6bb5\u4ee3\u7801\uff0c\u6211\u4eec\u5fc5\u987b\u8981\u5148\u641e\u61c2Promise [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":6282,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[274],"tags":[],"_links":{"self":[{"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/posts\/6486"}],"collection":[{"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lilichao.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6486"}],"version-history":[{"count":2,"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/posts\/6486\/revisions"}],"predecessor-version":[{"id":6488,"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/posts\/6486\/revisions\/6488"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lilichao.com\/index.php?rest_route=\/wp\/v2\/media\/6282"}],"wp:attachment":[{"href":"https:\/\/lilichao.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6486"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lilichao.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6486"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lilichao.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6486"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}