{"id":62144,"date":"2026-01-19T12:49:44","date_gmt":"2026-01-19T04:49:44","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/62144.html"},"modified":"2026-01-19T12:49:44","modified_gmt":"2026-01-19T04:49:44","slug":"%e6%b7%b1%e5%85%a5%e7%90%86%e8%a7%a3-javascript-%e5%bc%82%e6%ad%a5%e7%bc%96%e7%a8%8b%ef%bc%9a%e4%bb%8e-event-loop-%e5%88%b0-promise","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/62144.html","title":{"rendered":"\u6df1\u5165\u7406\u89e3 JavaScript \u5f02\u6b65\u7f16\u7a0b\uff1a\u4ece Event Loop \u5230 Promise"},"content":{"rendered":"

\u4e2a\u4eba\u7a7a\u95f4：<\/span>https:\/\/blog.csdn.net\/m0_73589512<\/span>https:\/\/blog.csdn.net\/m0_73589512<\/span><\/span><\/p>\n

\u5927\u5bb6\u597d，\u6211\u662f\u53c1\u4f70\u4e07~~<\/span><\/p>\n

\u5982\u679c\u672c\u6587\u5bf9\u60a8\u6709\u5e2e\u52a9，\u8bf7\u732e\u4e0a\u4f60\u7684\u5c0f\u2765(^_-)\u54df~~~<\/span><\/p>\n

\u4f5c\u4e3a\u524d\u7aef\u5f00\u53d1\u8005，\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u548c JavaScript \u7684\u5f02\u6b65\u7279\u6027\u6253\u4ea4\u9053 \u2014\u2014 \u5b9a\u65f6\u5668\u3001\u7f51\u7edc\u8bf7\u6c42\u3001\u4e8b\u4ef6\u56de\u8c03\u2026\u2026 \u4f46\u4f60\u771f\u7684\u7406\u89e3 JS \u5355\u7ebf\u7a0b\u4e0b\u7684\u5f02\u6b65\u5e95\u5c42\u903b\u8f91\u5417？\u672c\u6587\u5c06\u4ece\u8fdb\u7a0b\u7ebf\u7a0b\u57fa\u7840\u8bb2\u8d77，\u4e00\u6b65\u6b65\u62c6\u89e3 Event Loop\u3001\u5b8f\u5fae\u4efb\u52a1\u3001Promise \u6838\u5fc3\u539f\u7406，\u5e2e\u4f60\u5f7b\u5e95\u641e\u61c2 JS \u5f02\u6b65\u7f16\u7a0b\u3002<\/p>\n

\u63a5\u7eed\u4e0a\u6587：https:\/\/blog.csdn.net\/m0_73589512\/article\/details\/157133111<\/span>https:\/\/blog.csdn.net\/m0_73589512\/article\/details\/157133111<\/span><\/span><\/p>\n

\u76ee\u5f55<\/p>\n

\u4e00\u3001\u57fa\u7840\u8ba4\u77e5：\u8fdb\u7a0b\u4e0e\u7ebf\u7a0b<\/p>\n

\u4e8c\u3001\u6838\u5fc3\u673a\u5236：Event Loop（\u4e8b\u4ef6\u5faa\u73af）<\/p>\n

2.1 \u540c\u6b65\u4e0e\u5f02\u6b65\u7684\u672c\u8d28<\/p>\n

2.2 \u5b8f\u4efb\u52a1\u4e0e\u5fae\u4efb\u52a1<\/p>\n

Event Loop \u5b8c\u6574\u6267\u884c\u6d41\u7a0b<\/p>\n

\u4e09\u3001\u5f02\u6b65\u89e3\u51b3\u65b9\u6848：Promise<\/p>\n

3.1 Promise \u6838\u5fc3\u7279\u6027<\/p>\n

3.2 Promise \u5e38\u7528\u9759\u6001\u65b9\u6cd5<\/p>\n

3.3 \u624b\u5199 Promise（\u6838\u5fc3\u5b9e\u73b0）<\/p>\n

\u56db\u3001\u8bed\u6cd5\u7cd6：async\/await<\/p>\n

\u6838\u5fc3\u7279\u70b9<\/p>\n

\u4e94\u3001\u603b\u7ed3<\/p>\n

\n

\u4e00\u3001\u57fa\u7840\u8ba4\u77e5：\u8fdb\u7a0b\u4e0e\u7ebf\u7a0b<\/h3>\n

\u8981\u7406\u89e3 JS \u5f02\u6b65，\u9996\u5148\u5f97\u641e\u6e05\u695a\u300c\u8fdb\u7a0b\u300d\u548c\u300c\u7ebf\u7a0b\u300d\u8fd9\u4e24\u4e2a\u57fa\u7840\u6982\u5ff5，\u8fd9\u662f\u6d4f\u89c8\u5668\u5b9e\u73b0\u5f02\u6b65\u7684\u786c\u4ef6\u5e95\u5c42\u652f\u6491\u3002<\/p>\n\n\u5bf9\u6bd4\u7ef4\u5ea6\u8fdb\u7a0b\u7ebf\u7a0b<\/tr>\n\n\n\n\n\n
\u901a\u4fd7\u7c7b\u6bd4<\/td>\n\u5de5\u5382\u91cc\u7684\u72ec\u7acb\u8f66\u95f4<\/td>\n\u8f66\u95f4\u91cc\u7684\u5de5\u4eba<\/td>\n<\/tr>\n
\u6838\u5fc3\u5b9a\u4f4d<\/td>\nCPU \u8d44\u6e90\u5206\u914d\u7684\u6700\u5c0f\u5355\u4f4d<\/td>\nCPU \u8c03\u5ea6\u6267\u884c\u7684\u6700\u5c0f\u5355\u4f4d<\/td>\n<\/tr>\n
\u6210\u672c\u7279\u6027<\/td>\n\u521b\u5efa \/ \u9500\u6bc1\u6210\u672c\u9ad8（\u91cd\u91cf\u7ea7）<\/td>\n\u521b\u5efa \/ \u9500\u6bc1\u6210\u672c\u4f4e（\u8f7b\u91cf\u7ea7）<\/td>\n<\/tr>\n
\u524d\u7aef\u793a\u4f8b<\/td>\n\u6d4f\u89c8\u5668\u6bcf\u65b0\u5f00\u4e00\u4e2a\u6807\u7b7e\u9875 = \u65b0\u8fdb\u7a0b<\/td>\n\u6d4f\u89c8\u5668\u8fdb\u7a0b\u5185\u5305\u542b\u591a\u7ebf\u7a0b：GUI \u6e32\u67d3\u7ebf\u7a0b\u3001JS \u5f15\u64ce\u7ebf\u7a0b\u3001\u5b9a\u65f6\u5668\u7ebf\u7a0b\u3001\u5f02\u6b65 HTTP \u8bf7\u6c42\u7ebf\u7a0b\u3001\u4e8b\u4ef6\u89e6\u53d1\u7ebf\u7a0b<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u8fd9\u91cc\u6709\u4e2a\u5173\u952e\u77e5\u8bc6\u70b9：JavaScript \u662f\u5355\u7ebf\u7a0b\u811a\u672c\u8bed\u8a00，\u4f46\u6d4f\u89c8\u5668\u662f\u591a\u7ebf\u7a0b\u3001\u591a\u8fdb\u7a0b\u7684\u3002JS \u7684\u5355\u7ebf\u7a0b\u610f\u5473\u7740\u5b83\u540c\u4e00\u65f6\u95f4\u53ea\u80fd\u505a\u4e00\u4ef6\u4e8b，\u800c\u6d4f\u89c8\u5668\u7684\u591a\u7ebf\u7a0b\u5219\u4e3a JS \u5b9e\u73b0\u5f02\u6b65\u63d0\u4f9b\u4e86\u57fa\u7840\u3002<\/p>\n

\u4e8c\u3001\u6838\u5fc3\u673a\u5236：Event Loop（\u4e8b\u4ef6\u5faa\u73af）<\/h3>\n

JS \u5355\u7ebf\u7a0b\u8981\u5904\u7406\u540c\u6b65\u548c\u5f02\u6b65\u4efb\u52a1，\u5168\u9760 Event Loop \u8fd9\u4e2a\u6838\u5fc3\u673a\u5236\u3002\u6211\u4eec\u5148\u62c6\u89e3\u5b83\u7684\u6267\u884c\u903b\u8f91\u3002<\/p>\n

2.1 \u540c\u6b65\u4e0e\u5f02\u6b65\u7684\u672c\u8d28<\/h4>\n
    \n
  • \u540c\u6b65\u4ee3\u7801：\u6309\u987a\u5e8f\u6267\u884c，\u4f1a\u963b\u585e\u540e\u7eed\u4ee3\u7801（\u6bd4\u5982\u666e\u901a\u7684console.log\u3001\u53d8\u91cf\u58f0\u660e）；<\/li>\n
  • \u5f02\u6b65\u4ee3\u7801：\u4e0d\u963b\u585e\u4e3b\u7ebf\u7a0b，\u8fdb\u5165\u300c\u4efb\u52a1\u961f\u5217\u300d\u7b49\u5f85\u6267\u884c（\u6bd4\u5982setTimeout\u3001\u7f51\u7edc\u8bf7\u6c42）\u3002<\/li>\n<\/ul>\n

    \u4e3e\u4e2a\u7b80\u5355\u4f8b\u5b50：<\/p>\n

    \/\/ \u540c\u6b65\u4ee3\u7801：\u987a\u5e8f\u6267\u884c
    \nconsole.log('1');
    \nconsole.log('2');<\/p>\n

    \/\/ \u5f02\u6b65\u4ee3\u7801：\u5148\u6267\u884c\u540c\u6b65，\u518d\u6267\u884c\u5f02\u6b65
    \nconsole.log('1');
    \nsetTimeout(() => console.log('2'), 0);
    \nconsole.log('3');
    \n\/\/ \u8f93\u51fa：1 \u2192 3 \u2192 2<\/p>\n

    2.2 \u5b8f\u4efb\u52a1\u4e0e\u5fae\u4efb\u52a1<\/h4>\n

    \u5f02\u6b65\u4efb\u52a1\u5e76\u975e\u300c\u4e00\u89c6\u540c\u4ec1\u300d，\u800c\u662f\u5206\u4e3a\u5b8f\u4efb\u52a1\u548c\u5fae\u4efb\u52a1，\u6267\u884c\u4f18\u5148\u7ea7\u6709\u660e\u786e\u533a\u5206：<\/p>\n

      \n
    • \u5b8f\u4efb\u52a1：\u811a\u672c\u4ee3\u7801\u672c\u8eab\u3001setTimeout\/setInterval\u3001I\/O \u64cd\u4f5c\u3001UI \u6e32\u67d3\u7b49；<\/li>\n
    • \u5fae\u4efb\u52a1：Promise.then\/catch\/finally\u3001queueMicrotask\u3001Node.js \u7684process.nextTick\u7b49\u3002<\/li>\n<\/ul>\n
      Event Loop \u5b8c\u6574\u6267\u884c\u6d41\u7a0b<\/h5>\n
    • \u6267\u884c\u8c03\u7528\u6808\u4e2d\u7684\u540c\u6b65\u4ee3\u7801（\u5b8f\u4efb\u52a1\u7684\u4e00\u90e8\u5206）；<\/li>\n
    • \u6267\u884c\u5b8c\u540c\u6b65\u4ee3\u7801\u540e，\u6e05\u7a7a\u6240\u6709\u5fae\u4efb\u52a1\u961f\u5217（\u6309\u987a\u5e8f\u6267\u884c）；<\/li>\n
    • \u5982\u6709\u9700\u8981，\u6267\u884c UI \u6e32\u67d3；<\/li>\n
    • \u4ece\u5b8f\u4efb\u52a1\u961f\u5217\u4e2d\u53d6\u51fa\u4e00\u4e2a\u5b8f\u4efb\u52a1\u6267\u884c；<\/li>\n
    • \u91cd\u590d\u6b65\u9aa4 2-4，\u5f62\u6210\u300c\u4e8b\u4ef6\u5faa\u73af\u300d\u3002<\/li>\n

      \u6838\u5fc3\u539f\u5219：\u5148\u540c\u6b65，\u518d\u5fae\u4efb\u52a1，\u6700\u540e\u5b8f\u4efb\u52a1；\u6bcf\u6b21\u6267\u884c\u5b8c\u4e00\u4e2a\u5b8f\u4efb\u52a1，\u90fd\u8981\u6e05\u7a7a\u5fae\u4efb\u52a1\u961f\u5217\u3002<\/p>\n

      \u4e09\u3001\u5f02\u6b65\u89e3\u51b3\u65b9\u6848：Promise<\/h3>\n

      \u65e9\u671f\u5f02\u6b65\u7f16\u7a0b\u4f9d\u8d56\u5d4c\u5957\u56de\u8c03\u51fd\u6570，\u5bb9\u6613\u5f62\u6210\u300c\u56de\u8c03\u5730\u72f1\u300d（\u91d1\u5b57\u5854\u5f62\u4ee3\u7801\u3001\u9519\u8bef\u5904\u7406\u56f0\u96be\u3001\u590d\u7528\u6027\u5dee），\u800c Promise \u662f\u89e3\u51b3\u56de\u8c03\u5730\u72f1\u7684\u6807\u51c6\u65b9\u6848\u3002<\/p>\n

      3.1 Promise \u6838\u5fc3\u7279\u6027<\/h4>\n
    • \n

      \u4e09\u79cd\u72b6\u6001：<\/p>\n

        \n
      • pending：\u9ed8\u8ba4\u72b6\u6001（\u7b49\u5f85\u4e2d）；<\/li>\n
      • fulfilled：\u6210\u529f\u72b6\u6001（\u4e0d\u53ef\u9006）；<\/li>\n
      • rejected：\u5931\u8d25\u72b6\u6001（\u4e0d\u53ef\u9006）\u3002\u72b6\u6001\u53ea\u80fd\u4ecepending\u8f6c\u4e3afulfilled\u6216rejected，\u4e00\u65e6\u6539\u53d8\u5c31\u65e0\u6cd5\u4fee\u6539\u3002<\/li>\n<\/ul>\n<\/li>\n
      • \n

        \u94fe\u5f0f\u8c03\u7528：Promise \u7684then\u65b9\u6cd5\u4f1a\u8fd4\u56de\u65b0\u7684 Promise，\u652f\u6301\u94fe\u5f0f\u8c03\u7528，\u66ff\u4ee3\u5d4c\u5957\u56de\u8c03：<\/p>\n

        \/\/ \u6a21\u62df\u5f02\u6b65\u8bf7\u6c42
        \nfunction fetchUser(id) {
        \n return new Promise(resolve => {
        \n setTimeout(() => resolve({ id, name: `\u7528\u6237${id}` }), 1000);
        \n });
        \n}<\/p>\n

        function fetchPosts(userId) {
        \n return new Promise(resolve => {
        \n setTimeout(() => resolve([`\u5e16\u5b501-${userId}`, `\u5e16\u5b502-${userId}`]), 1000);
        \n });
        \n}<\/p>\n

        \/\/ \u94fe\u5f0f\u8c03\u7528：\u66ff\u4ee3\u5d4c\u5957
        \nfetchUser(1)
        \n .then(user => {
        \n console.log('\u7528\u6237:', user);
        \n return fetchPosts(user.id); \/\/ \u8fd4\u56de\u65b0Promise
        \n })
        \n .then(posts => console.log('\u5e16\u5b50:', posts))
        \n .catch(error => console.error('\u9519\u8bef:', error));\n <\/li>\n

        3.2 Promise \u5e38\u7528\u9759\u6001\u65b9\u6cd5<\/h4>\n

        Promise \u63d0\u4f9b\u4e86\u591a\u4e2a\u9759\u6001\u65b9\u6cd5，\u6ee1\u8db3\u4e0d\u540c\u7684\u5f02\u6b65\u573a\u666f\u9700\u6c42：<\/p>\n

          \n
        • Promise.all：\u6240\u6709 Promise \u90fd\u6210\u529f\u624d\u8fd4\u56de\u6210\u529f，\u4e00\u4e2a\u5931\u8d25\u5219\u6574\u4f53\u5931\u8d25；<\/li>\n
        • Promise.race：\u591a\u4e2a Promise \u4e2d\u300c\u6700\u5feb\u5b8c\u6210\u300d\u7684\u90a3\u4e2a\u51b3\u5b9a\u7ed3\u679c（\u65e0\u8bba\u6210\u529f \/ \u5931\u8d25）；<\/li>\n
        • Promise.allSettled：\u7b49\u5f85\u6240\u6709 Promise \u5b8c\u6210（\u65e0\u8bba\u6210\u529f \/ \u5931\u8d25），\u8fd4\u56de\u6bcf\u4e2a Promise \u7684\u7ed3\u679c；<\/li>\n
        • Promise.any：\u53ea\u8981\u6709\u4e00\u4e2a Promise \u6210\u529f\u5c31\u8fd4\u56de\u6210\u529f，\u5168\u90e8\u5931\u8d25\u624d\u8fd4\u56de\u5931\u8d25\u3002<\/li>\n<\/ul>\n

          \u793a\u4f8b\u4ee3\u7801：<\/p>\n

          \/\/ Promise.all：\u6279\u91cf\u8bf7\u6c42
          \nPromise.all([fetchUser(1), fetchUser(2)])
          \n .then(users => console.log('\u6240\u6709\u7528\u6237:', users))
          \n .catch(err => console.error('\u5355\u4e2a\u5931\u8d25:', err));<\/p>\n

          \/\/ Promise.race：\u8d85\u65f6\u63a7\u5236
          \nPromise.race([
          \n fetchUser(1),
          \n new Promise((_, reject) => setTimeout(() => reject('\u8bf7\u6c42\u8d85\u65f6'), 800))
          \n])
          \n.then(user => console.log('\u8bf7\u6c42\u6210\u529f:', user))
          \n.catch(err => console.error('\u8bf7\u6c42\u5931\u8d25:', err));<\/p>\n

          3.3 \u624b\u5199 Promise（\u6838\u5fc3\u5b9e\u73b0）<\/h4>\n

          \u7406\u89e3 Promise \u6700\u597d\u7684\u65b9\u5f0f\u662f\u624b\u5199\u4e00\u4e2a\u7b80\u6613\u7248，\u6838\u5fc3\u903b\u8f91\u5305\u62ec\u72b6\u6001\u7ba1\u7406\u3001\u56de\u8c03\u961f\u5217\u3001then \u65b9\u6cd5\u94fe\u5f0f\u8c03\u7528：<\/p>\n

          const PENDING = 'PENDING';
          \nconst FULFILLED = 'FULFILLED';
          \nconst REJECTED = 'REJECTED';<\/p>\n

          class MyPromise {
          \n constructor(executor) {
          \n this.status = PENDING; \/\/ \u9ed8\u8ba4\u72b6\u6001
          \n this.value = undefined; \/\/ \u6210\u529f\u503c
          \n this.reason = undefined; \/\/ \u5931\u8d25\u539f\u56e0
          \n this.onResolvedCallbacks = []; \/\/ \u6210\u529f\u56de\u8c03\u961f\u5217
          \n this.onRejectedCallbacks = []; \/\/ \u5931\u8d25\u56de\u8c03\u961f\u5217<\/p>\n

          \/\/ \u6210\u529f\u56de\u8c03
          \n const resolve = (value) => {
          \n if (this.status === PENDING) {
          \n this.status = FULFILLED;
          \n this.value = value;
          \n this.onResolvedCallbacks.forEach(fn => fn());
          \n }
          \n };<\/p>\n

          \/\/ \u5931\u8d25\u56de\u8c03
          \n const reject = (reason) => {
          \n if (this.status === PENDING) {
          \n this.status = REJECTED;
          \n this.reason = reason;
          \n this.onRejectedCallbacks.forEach(fn => fn());
          \n }
          \n };<\/p>\n

          try {
          \n executor(resolve, reject); \/\/ \u7acb\u5373\u6267\u884c\u6267\u884c\u5668
          \n } catch (error) {
          \n reject(error);
          \n }
          \n }<\/p>\n

          then(onFulfilled, onRejected) {
          \n \/\/ \u5904\u7406\u9ed8\u8ba4\u56de\u8c03
          \n onFulfilled = typeof onFulfilled === 'function' ? onFulfilled : v => v;
          \n onRejected = typeof onRejected === 'function' ? onRejected : e => { throw e };<\/p>\n

          const promise2 = new MyPromise((resolve, reject) => {
          \n if (this.status === FULFILLED) {
          \n setTimeout(() => {
          \n try {
          \n const x = onFulfilled(this.value);
          \n this.resolvePromise(promise2, x, resolve, reject);
          \n } catch (e) {
          \n reject(e);
          \n }
          \n }, 0);
          \n }<\/p>\n

          if (this.status === REJECTED) {
          \n setTimeout(() => {
          \n try {
          \n const x = onRejected(this.reason);
          \n this.resolvePromise(promise2, x, resolve, reject);
          \n } catch (e) {
          \n reject(e);
          \n }
          \n }, 0);
          \n }<\/p>\n

          if (this.status === PENDING) {
          \n this.onResolvedCallbacks.push(() => {
          \n setTimeout(() => {
          \n try {
          \n const x = onFulfilled(this.value);
          \n this.resolvePromise(promise2, x, resolve, reject);
          \n } catch (e) {
          \n reject(e);
          \n }
          \n }, 0);
          \n });
          \n this.onRejectedCallbacks.push(() => {
          \n setTimeout(() => {
          \n try {
          \n const x = onRejected(this.reason);
          \n this.resolvePromise(promise2, x, resolve, reject);
          \n } catch (e) {
          \n reject(e);
          \n }
          \n }, 0);
          \n });
          \n }
          \n });<\/p>\n

          return promise2;
          \n }<\/p>\n

          \/\/ \u89e3\u6790Promise\u8fd4\u56de\u503c（\u6838\u5fc3\u903b\u8f91）
          \n resolvePromise(promise2, x, resolve, reject) {
          \n if (promise2 === x) {
          \n return reject(new TypeError('\u5faa\u73af\u5f15\u7528'));
          \n }
          \n let called = false;
          \n if (x instanceof MyPromise) {
          \n x.then(y => this.resolvePromise(promise2, y, resolve, reject), reject);
          \n } else if (x !== null && (typeof x === 'object' || typeof x === 'function')) {
          \n try {
          \n const then = x.then;
          \n if (typeof then === 'function') {
          \n then.call(x, y => {
          \n if (called) return;
          \n called = true;
          \n this.resolvePromise(promise2, y, resolve, reject);
          \n }, e => {
          \n if (called) return;
          \n called = true;
          \n reject(e);
          \n });
          \n } else {
          \n resolve(x);
          \n }
          \n } catch (e) {
          \n if (called) return;
          \n called = true;
          \n reject(e);
          \n }
          \n } else {
          \n resolve(x);
          \n }
          \n }<\/p>\n

          catch(onRejected) {
          \n return this.then(null, onRejected);
          \n }
          \n}<\/p>\n

          \u56db\u3001\u8bed\u6cd5\u7cd6：async\/await<\/h3>\n

          async\/await\u662f Promise \u7684\u8bed\u6cd5\u7cd6，\u5b83\u8ba9\u5f02\u6b65\u4ee3\u7801\u770b\u8d77\u6765\u50cf\u540c\u6b65\u4ee3\u7801，\u5e95\u5c42\u4f9d\u7136\u57fa\u4e8e Promise \u5b9e\u73b0\u3002<\/p>\n

          \u6838\u5fc3\u7279\u70b9<\/h4>\n
        • async\u51fd\u6570：\u58f0\u660e\u540e\u8fd4\u56de\u503c\u81ea\u52a8\u5305\u88c5\u4e3a Promise；<\/li>\n
        • await\u5173\u952e\u5b57：\u53ea\u80fd\u5728 async \u51fd\u6570\u5185\u4f7f\u7528，\u7b49\u5f85 Promise \u5b8c\u6210\u5e76\u8fd4\u56de\u7ed3\u679c；<\/li>\n
        • \u9519\u8bef\u5904\u7406：\u53ef\u901a\u8fc7try\/catch\u6355\u83b7\u5f02\u6b65\u9519\u8bef，\u66f4\u7b26\u5408\u540c\u6b65\u4ee3\u7801\u7684\u5199\u6cd5\u3002<\/li>\n

          \u793a\u4f8b：<\/p>\n

          async function fetchData() {
          \n try {
          \n const user = await fetchUser(1);
          \n console.log('\u7528\u6237:', user);
          \n const posts = await fetchPosts(user.id);
          \n console.log('\u5e16\u5b50:', posts);
          \n return posts;
          \n } catch (error) {
          \n console.error('\u8bf7\u6c42\u5931\u8d25:', error);
          \n }
          \n}<\/p>\n

          fetchData();<\/p>\n

          \u4e94\u3001\u603b\u7ed3<\/h3>\n

          JavaScript \u7684\u5f02\u6b65\u7f16\u7a0b\u4f53\u7cfb\u53ef\u4ee5\u603b\u7ed3\u4e3a：<\/p>\n

        • \u5e95\u5c42\u652f\u6491：\u6d4f\u89c8\u5668\u591a\u8fdb\u7a0b \/ \u591a\u7ebf\u7a0b\u4e3a JS \u5355\u7ebf\u7a0b\u63d0\u4f9b\u5f02\u6b65\u80fd\u529b；<\/li>\n
        • \u6838\u5fc3\u673a\u5236：Event Loop \u901a\u8fc7\u5b8f\u4efb\u52a1 \/ \u5fae\u4efb\u52a1\u961f\u5217\u5b9e\u73b0\u5f02\u6b65\u8c03\u5ea6；<\/li>\n
        • \u89e3\u51b3\u65b9\u6848：Promise \u89e3\u51b3\u56de\u8c03\u5730\u72f1，async\/await \u8ba9 Promise \u5199\u6cd5\u66f4\u4f18\u96c5\u3002<\/li>\n

          \u7406\u89e3\u8fd9\u4e9b\u6838\u5fc3\u6982\u5ff5，\u4e0d\u4ec5\u80fd\u5e2e\u4f60\u641e\u5b9a\u9762\u8bd5\u4e2d\u7684\u5f02\u6b65\u9ad8\u9891\u9898，\u66f4\u80fd\u8ba9\u4f60\u5728\u5b9e\u9645\u5f00\u53d1\u4e2d\u7cbe\u51c6\u5b9a\u4f4d\u5f02\u6b65\u76f8\u5173\u7684 bug（\u6bd4\u5982\u5b9a\u65f6\u5668\u8bef\u5dee\u3001\u5b8f\u5fae\u4efb\u52a1\u6267\u884c\u987a\u5e8f\u95ee\u9898）\u3002\u5f02\u6b65\u662f JS \u7684\u6838\u5fc3，\u4e5f\u662f\u524d\u7aef\u8fdb\u9636\u7684\u5fc5\u7ecf\u4e4b\u8def，\u5e0c\u671b\u8fd9\u7bc7\u6587\u7ae0\u80fd\u5e2e\u4f60\u5efa\u7acb\u6e05\u6670\u7684\u77e5\u8bc6\u4f53\u7cfb\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

          \u4e2a\u4eba\u7a7a\u95f4：https:\/\/blog.csdn.net\/m0_73589512https:\/\/blog.csdn.net\/m0_73589512
          \n\u5927\u5bb6\u597d，\u6211\u662f\u53c1\u4f70\u4e07~~
          \n\u5982\u679c\u672c\u6587\u5bf9\u60a8\u6709\u5e2e\u52a9，\u8bf7\u732e\u4e0a\u4f60\u7684\u5c0f\u2765(^_-)\u54df~~~
          \n\u4f5c\u4e3a\u524d\u7aef\u5f00\u53d1\u8005，\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u548c JavaScript \u7684\u5f02\u6b65\u7279\u6027\u6253\u4ea4\u9053 \u2014\u2014 \u5b9a\u65f6\u5668\u3001\u7f51\u7edc\u8bf7\u6c42\u3001\u4e8b\u4ef6\u56de\u8c03\u2026\u2026 \u4f46\u4f60\u771f\u7684\u7406\u89e3 JS \u5355\u7ebf\u7a0b\u4e0b\u7684\u5f02\u6b65\u5e95\u5c42\u903b\u8f91\u5417？\u672c\u6587\u5c06\u4ece\u8fdb\u7a0b\u7ebf\u7a0b\u57fa\u7840\u8bb2\u8d77&<\/p>\n","protected":false},"author":2,"featured_media":62143,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[187,87,190],"topic":[],"class_list":["post-62144","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-javascript","tag-87","tag-190"],"yoast_head":"\n\u6df1\u5165\u7406\u89e3 JavaScript \u5f02\u6b65\u7f16\u7a0b\uff1a\u4ece Event Loop \u5230 Promise - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/62144.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u6df1\u5165\u7406\u89e3 JavaScript \u5f02\u6b65\u7f16\u7a0b\uff1a\u4ece Event Loop \u5230 Promise - 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