{"id":5646,"date":"2017-01-18T14:18:03","date_gmt":"2017-01-18T06:18:03","guid":{"rendered":"https:\/\/sdeno.com\/?p=5646"},"modified":"2017-01-18T14:29:00","modified_gmt":"2017-01-18T06:29:00","slug":"settimeout-%e7%a7%98%e5%af%86","status":"publish","type":"post","link":"https:\/\/sdeno.com\/?p=5646","title":{"rendered":"setTimeout \u79d8\u5bc6"},"content":{"rendered":"

\u63cf\u8ff0\uff1a\u8ba1\u65f6\u5668setTimeout\u662f\u6211\u4eec\u7ecf\u5e38\u4f1a\u7528\u5230\u7684\uff0c\u5b83\u7528\u4e8e\u5728\u6307\u5b9a\u7684\u6beb\u79d2\u6570\u540e\u8c03\u7528\u51fd\u6570\u6216\u8ba1\u7b97\u8868\u8fbe\u5f0f\u3002<\/span><\/p>\n

\u8bed\u6cd5\uff1asetTimeout(code, millisec, args)<\/p>\n

\u6ce8\u610f\uff1a\u5982\u679ccode\u4e3a\u5b57\u7b26\u4e32\uff0c\u76f8\u5f53\u4e8e\u6267\u884ceval()\u65b9\u6cd5\u6765\u6267\u884ccode\u3002<\/p>\n

\u5f53\u7136\uff0c\u8fd9\u4e00\u7bc7\u6587\u7ae0\u5e76\u4e0d\u4ec5\u4ec5\u544a\u8bc9\u4f60\u600e\u4e48\u7528setTimeout\uff0c\u800c\u4e14\u7406\u89e3\u5176\u662f\u5982\u4f55\u6267\u884c\u7684\u3002<\/p>\n

 <\/p>\n

1\u3001setTimeout\u539f\u7406<\/strong><\/p>\n

var start = new Date(); \r\nvar end = 0; \r\nsetTimeout(function() { \r\n console.log(new Date() - start); \r\n}, 500); \r\nwhile (new Date() - start <= 1000) {}<\/pre>\n
\u5728\u4e0a\u9762\u7684\u4ee3\u7801\u4e2d\uff0c\u5b9a\u4e49\u4e86\u4e00\u4e2asetTimeout\u5b9a\u65f6\u5668\uff0c\u5ef6\u65f6\u65f6\u95f4\u662f500\u6beb\u79d2\u3002<\/p>\n
\u4f60\u662f\u4e0d\u662f\u89c9\u5f97\u6253\u5370\u7ed3\u679c\u662f\uff1a 500<\/p>\n
\u53ef\u4e8b\u5b9e\u5374\u662f\u51fa\u4e4e\u4f60\u7684\u610f\u6599\uff0c\u6253\u5370\u7ed3\u679c\u662f\u8fd9\u6837\u7684\uff08\u4e5f\u8bb8\u4f60\u6253\u5370\u51fa\u6765\u4f1a\u4e0d\u4e00\u6837\uff0c\u4f46\u80af\u5b9a\u4f1a\u5927\u4e8e1000\u6beb\u79d2\uff09\uff1a<\/p>\n
<\/div>
<\/div><\/div><\/div>\"QQ20170118-141840@2x\"<\/figure>\n
\u8fd9\u662f\u4e3a\u6bdb\u5462\uff1f<\/p>\n
\u7a76\u5176\u539f\u56e0\uff0c\u8fd9\u662f\u56e0\u4e3a JavaScript\u662f\u5355\u7ebf\u7a0b\u6267\u884c\u7684\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u5728\u4efb\u4f55\u65f6\u95f4\u70b9\uff0c\u6709\u4e14\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u5728\u8fd0\u884cJavaScript\u7a0b\u5e8f\uff0c\u65e0\u6cd5\u540c\u4e00\u65f6\u5019\u8fd0\u884c\u591a\u6bb5\u4ee3\u7801\u3002<\/p>\n
\u518d\u6765\u770b\u770b\u6d4f\u89c8\u5668\u4e0b\u7684JavaScript\u3002<\/p>\n
\u6d4f\u89c8\u5668\u7684\u5185\u6838\u662f\u591a\u7ebf\u7a0b\u7684\uff0c\u5b83\u4eec\u5728\u5185\u6838\u63a7\u5236\u4e0b\u76f8\u4e92\u914d\u5408\u4ee5\u4fdd\u6301\u540c\u6b65\uff0c\u4e00\u4e2a\u6d4f\u89c8\u5668\u81f3\u5c11\u5b9e\u73b0\u4e09\u4e2a\u5e38\u9a7b\u7ebf\u7a0b\uff1aJavaScript\u5f15\u64ce\u7ebf\u7a0b\uff0cGUI\u6e32\u67d3\u7ebf\u7a0b\uff0c\u6d4f\u89c8\u5668\u4e8b\u4ef6\u89e6\u53d1\u7ebf\u7a0b\u3002<\/p>\n
    \n
  • JavaScript\u5f15\u64ce\u662f\u57fa\u4e8e\u4e8b\u4ef6\u9a71\u52a8\u5355\u7ebf\u7a0b\u6267\u884c\u7684\uff0cJavaScript\u5f15\u64ce\u4e00\u76f4\u7b49\u5f85\u7740\u4efb\u52a1\u961f\u5217\u4e2d\u4efb\u52a1\u7684\u5230\u6765\uff0c\u7136\u540e\u52a0\u4ee5\u5904\u7406\uff0c\u6d4f\u89c8\u5668\u65e0\u8bba\u4ec0\u4e48\u65f6\u5019\u90fd\u53ea\u6709\u4e00\u4e2aJavaScript\u7ebf\u7a0b\u5728\u8fd0\u884cJavaScript\u7a0b\u5e8f\u3002<\/li>\n
  • GUI\u6e32\u67d3\u7ebf\u7a0b\u8d1f\u8d23\u6e32\u67d3\u6d4f\u89c8\u5668\u754c\u9762\uff0c\u5f53\u754c\u9762\u9700\u8981\u91cd\u7ed8\uff08Repaint\uff09\u6216\u7531\u4e8e\u67d0\u79cd\u64cd\u4f5c\u5f15\u53d1\u56de\u6d41(Reflow)\u65f6\uff0c\u8be5\u7ebf\u7a0b\u5c31\u4f1a\u6267\u884c\u3002\u4f46\u9700\u8981\u6ce8\u610f\uff0cGUI\u6e32\u67d3\u7ebf\u7a0b\u4e0eJavaScript\u5f15\u64ce\u662f\u4e92\u65a5\u7684\uff0c\u5f53JavaScript\u5f15\u64ce\u6267\u884c\u65f6GUI\u7ebf\u7a0b\u4f1a\u88ab\u6302\u8d77\uff0cGUI\u66f4\u65b0\u4f1a\u88ab\u4fdd\u5b58\u5728\u4e00\u4e2a\u961f\u5217\u4e2d\u7b49\u5230JavaScript\u5f15\u64ce\u7a7a\u95f2\u65f6\u7acb\u5373\u88ab\u6267\u884c\u3002<\/li>\n
  • \u4e8b\u4ef6\u89e6\u53d1\u7ebf\u7a0b\uff0c\u5f53\u4e00\u4e2a\u4e8b\u4ef6\u88ab\u89e6\u53d1\u65f6\uff0c\u8be5\u7ebf\u7a0b\u4f1a\u628a\u4e8b\u4ef6\u6dfb\u52a0\u5230\u5f85\u5904\u7406\u961f\u5217\u7684\u961f\u5c3e\uff0c\u7b49\u5f85JavaScript\u5f15\u64ce\u7684\u5904\u7406\u3002\u8fd9\u4e9b\u4e8b\u4ef6\u53ef\u6765\u81eaJavaScript\u5f15\u64ce\u5f53\u524d\u6267\u884c\u7684\u4ee3\u7801\u5757\u5982setTimeout\u3001\u4e5f\u53ef\u6765\u81ea\u6d4f\u89c8\u5668\u5185\u6838\u7684\u5176\u4ed6\u7ebf\u7a0b\u5982\u9f20\u6807\u70b9\u51fb\u3001Ajax\u5f02\u6b65\u8bf7\u6c42\u7b49\uff0c\u4f46\u7531\u4e8eJavaScript\u7684\u5355\u7ebf\u7a0b\u5173\u7cfb\uff0c\u6240\u6709\u8fd9\u4e9b\u4e8b\u4ef6\u90fd\u5f97\u6392\u961f\u7b49\u5f85JavaScript\u5f15\u64ce\u5904\u7406\uff08\u5f53\u7ebf\u7a0b\u4e2d\u6ca1\u6709\u6267\u884c\u4efb\u4f55\u540c\u6b65\u4ee3\u7801\u7684\u524d\u63d0\u4e0b\u624d\u4f1a\u6267\u884c\u5f02\u6b65\u4ee3\u7801\uff09\u3002<\/li>\n<\/ul>\n
     <\/p>\n
    \u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u518d\u6765\u56de\u987e\u4e00\u4e0b\u6700\u521d\u7684\u4f8b\u5b50\uff1a<\/p>\n
    var start = new Date(); \r\n \r\nvar end = 0; \r\n \r\nsetTimeout(function() { \r\n \r\n console.log(new Date() - start); \r\n \r\n}, 500); \r\n \r\nwhile (new Date() - start <= 1000) {}<\/pre>\n
    \u867d\u7136setTimeout\u7684\u5ef6\u65f6\u65f6\u95f4\u662f500\u6beb\u79d2\uff0c\u53ef\u662f\u7531\u4e8ewhile\u5faa\u73af\u7684\u5b58\u5728\uff0c\u53ea\u6709\u5f53\u95f4\u9694\u65f6\u95f4\u5927\u4e8e1000\u6beb\u79d2\u65f6\uff0c\u624d\u4f1a\u8df3\u51fawhile\u5faa\u73af\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u57281000\u6beb\u79d2\u4e4b\u524d\uff0cwhile\u5faa\u73af\u90fd\u5728\u5360\u636e\u7740JavaScript\u7ebf\u7a0b\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u53ea\u6709\u7b49\u5f85\u8df3\u51fawhile\u540e\uff0c\u7ebf\u7a0b\u624d\u4f1a\u7a7a\u95f2\u4e0b\u6765\uff0c\u624d\u4f1a\u53bb\u6267\u884c\u4e4b\u524d\u5b9a\u4e49\u7684setTimeout\u3002<\/p>\n
    \u6700\u540e \uff0c\u6211\u4eec\u53ef\u4ee5\u603b\u7ed3\u51fa\uff0csetTimeout\u53ea\u80fd\u4fdd\u8bc1\u5728\u6307\u5b9a\u7684\u65f6\u95f4\u540e\u5c06\u4efb\u52a1(\u9700\u8981\u6267\u884c\u7684\u51fd\u6570)\u63d2\u5165\u4efb\u52a1\u961f\u5217\u4e2d\u7b49\u5019\uff0c\u4f46\u662f\u4e0d\u4fdd\u8bc1\u8fd9\u4e2a\u4efb\u52a1\u5728\u4ec0\u4e48\u65f6\u5019\u6267\u884c\u3002\u4e00\u65e6\u6267\u884cjavascript\u7684\u7ebf\u7a0b\u7a7a\u95f2\u51fa\u6765\uff0c\u81ea\u884c\u4ece\u961f\u5217\u4e2d\u53d6\u51fa\u4efb\u52a1\u7136\u540e\u6267\u884c\u5b83\u3002<\/p>\n
    \u56e0\u4e3ajavascript\u7ebf\u7a0b\u5e76\u6ca1\u6709\u56e0\u4e3a\u4ec0\u4e48\u8017\u65f6\u64cd\u4f5c\u800c\u963b\u585e\uff0c\u6240\u4ee5\u53ef\u4ee5\u5f88\u5feb\u5730\u53d6\u51fa\u6392\u961f\u961f\u5217\u4e2d\u7684\u4efb\u52a1\u7136\u540e\u6267\u884c\u5b83\uff0c\u4e5f\u662f\u8fd9\u79cd\u961f\u5217\u673a\u5236\uff0c\u7ed9\u6211\u4eec\u5236\u9020\u4e00\u4e2a\u5f02\u6b65\u6267\u884c\u7684\u5047\u8c61\u3002<\/p>\n
     <\/p>\n
    2\u3001setTimeout\u7684\u597d\u642d\u6863\u201c0\u201d<\/strong><\/p>\n
    \u4e5f\u8bb8\u4f60\u89c1\u8fc7\u4e0b\u9762\u8fd9\u4e00\u6bb5\u4ee3\u7801\uff1a<\/p>\n
    setTimeout(function(){\r\n \r\n \/\/ statement\r\n \r\n}, 0);<\/pre>\n
    \u4e0a\u9762\u7684\u4ee3\u7801\u8868\u793a\u7acb\u5373\u6267\u884c\u3002<\/p>\n
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    \u4e0d\u540c\u7684\u6d4f\u89c8\u5668\u5b9e\u9645\u60c5\u51b5\u4e0d\u540c\uff0cIE8\u548c\u66f4\u65e9\u7684IE\u7684\u65f6\u95f4\u7cbe\u786e\u5ea6\u662f15.6ms\u3002\u4e0d\u8fc7\uff0c\u968f\u7740HTML5\u7684\u51fa\u73b0\uff0c\u5728\u9ad8\u7ea7\u7248\u672c\u7684\u6d4f\u89c8\u5668\uff08Chrome\u3001ie9+\u7b49\uff09\uff0c\u5b9a\u4e49\u7684\u6700\u5c0f\u65f6\u95f4\u95f4\u9694\u662f\u4e0d\u5f97\u4f4e\u4e8e4\u6beb\u79d2\uff0c\u5982\u679c\u4f4e\u4e8e\u8fd9\u4e2a\u503c\uff0c\u5c31\u4f1a\u81ea\u52a8\u589e\u52a0\uff0c\u5e76\u4e14\u57282010\u5e74\u53ca\u4e4b\u540e\u53d1\u5e03\u7684\u6d4f\u89c8\u5668\u4e2d\u91c7\u53d6\u4e00\u81f4\u3002<\/p>\n
    \u6240\u4ee5\u8bf4\uff0c\u5f53\u6211\u4eec\u5199\u4e3a setTimeout(fn,0) \u7684\u65f6\u5019\uff0c\u5b9e\u9645\u662f\u5b9e\u73b0\u63d2\u961f\u64cd\u4f5c\uff0c\u8981\u6c42\u6d4f\u89c8\u5668\u201c\u5c3d\u53ef\u80fd\u5feb\u201d\u7684\u8fdb\u884c\u56de\u8c03\uff0c\u4f46\u662f\u5b9e\u9645\u80fd\u591a\u5feb\u5c31\u5b8c\u5168\u53d6\u51b3\u4e8e\u6d4f\u89c8\u5668\u4e86\u3002<\/p>\n
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    \u901a\u8fc7\u8bbe\u7f6e\u4efb\u52a1\u5728\u5ef6\u8fdf\u52300s\u540e\u6267\u884c\uff0c\u5c31\u80fd\u6539\u53d8\u4efb\u52a1\u6267\u884c\u7684\u5148\u540e\u987a\u5e8f\uff0c\u5ef6\u8fdf\u8be5\u4efb\u52a1\u53d1\u751f\uff0c\u4f7f\u4e4b\u5f02\u6b65\u6267\u884c\u3002<\/p>\n
    \u6765\u770b\u4e00\u4e2a\u7f51\u4e0a\u5f88\u6d41\u884c\u7684\u4f8b\u5b50\uff1a<\/p>\n
    document.querySelector('#one input').onkeydown = function() { \r\n document.querySelector('#one span').innerHTML = this.value; \r\n}; \r\n \r\ndocument.querySelector('#second input').onkeydown = function() { \r\n setTimeout(function() { \r\n document.querySelector('#second span').innerHTML = document.querySelector('#second input').value; }, 0);\r\n};<\/pre>\n
    \u5f53\u4f60\u5f80\u4e24\u4e2a\u8868\u5355\u8f93\u5165\u5185\u5bb9\u65f6\uff0c\u4f60\u4f1a\u53d1\u73b0\u672a\u4f7f\u7528setTimeout\u51fd\u6570\u7684\u53ea\u4f1a\u83b7\u53d6\u5230\u8f93\u5165\u524d\u7684\u5185\u5bb9\uff0c\u800c\u4f7f\u7528setTimeout\u51fd\u6570\u7684\u5219\u4f1a\u83b7\u53d6\u5230\u8f93\u5165\u7684\u5185\u5bb9\u3002<\/p>\n
    \u8fd9\u662f\u4e3a\u4ec0\u4e48\u5462\uff1f<\/p>\n
    \u56e0\u4e3a\u5f53\u6309\u4e0b\u6309\u952e\u7684\u65f6\u5019\uff0cJavaScript \u5f15\u64ce\u9700\u8981\u6267\u884c keydown \u7684\u4e8b\u4ef6\u5904\u7406\u7a0b\u5e8f\uff0c\u7136\u540e\u66f4\u65b0\u6587\u672c\u6846\u7684 value \u503c\uff0c\u8fd9\u4e24\u4e2a\u4efb\u52a1\u4e5f\u9700\u8981\u6309\u987a\u5e8f\u6765\uff0c\u4e8b\u4ef6\u5904\u7406\u7a0b\u5e8f\u6267\u884c\u65f6\uff0c\u66f4\u65b0 value\u503c\uff08\u662f\u5728keypress\u540e\uff09\u7684\u4efb\u52a1\u5219\u8fdb\u5165\u961f\u5217\u7b49\u5f85\uff0c\u6240\u4ee5\u6211\u4eec\u5728 keydown \u7684\u4e8b\u4ef6\u5904\u7406\u7a0b\u5e8f\u91cc\u662f\u65e0\u6cd5\u5f97\u5230\u66f4\u65b0\u540e\u7684value\u7684\uff0c\u800c\u5229\u7528 setTimeout(fn, 0)\uff0c\u6211\u4eec\u628a\u53d6 value \u7684\u64cd\u4f5c\u653e\u5165\u961f\u5217\uff0c\u653e\u5728\u66f4\u65b0 value \u503c\u4ee5\u540e\uff0c\u8fd9\u6837\u4fbf\u53ef\u83b7\u53d6\u51fa\u6587\u672c\u6846\u7684\u503c\u3002<\/p>\n
    \u672a\u4f7f\u7528setTimeout\u51fd\u6570\uff0c\u6267\u884c\u987a\u5e8f\u662f\uff1aonkeydown => onkeypress => onkeyup<\/p>\n
    \u4f7f\u7528setTimeout\u51fd\u6570\uff0c\u6267\u884c\u987a\u5e8f\u662f\uff1aonkeydown => onkeypress => function => onkeyup<\/p>\n
    \u867d\u7136\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528keyup\u6765\u66ff\u4ee3keydown\uff0c\u4e0d\u8fc7\u6709\u4e00\u4e9b\u95ee\u9898\uff0c\u90a3\u5c31\u662f\u957f\u6309\u65f6\uff0ckeyup\u5e76\u4e0d\u4f1a\u89e6\u53d1\u3002<\/p>\n
    \u957f\u6309\u65f6\uff0ckeydown\u3001keypress\u3001keyup\u7684\u8c03\u7528\u987a\u5e8f\uff1a<\/p>\n
    keydown\r\n \r\nkeypress\r\n \r\nkeydown\r\n \r\nkeypress\r\n \r\n...\r\n \r\nkeyup<\/pre>\n
    \u4e5f\u5c31\u662f\u8bf4keyup\u53ea\u4f1a\u89e6\u53d1\u4e00\u6b21\uff0c\u6240\u4ee5\u4f60\u65e0\u6cd5\u7528keyup\u6765\u5b9e\u65f6\u83b7\u53d6\u503c\u3002<\/p>\n
    \u6211\u4eec\u8fd8\u53ef\u4ee5\u7528setImmediate()\u6765\u66ff\u4ee3setTimeout(fn,0)\uff1a<\/p>\n
    if (!window.setImmediate) { \r\n window.setImmediate = function(func, args){ \r\n return window.setTimeout(func, 0, args); \r\n }; \r\n \r\n window.clearImmediate = window.clearTimeout; \r\n}<\/pre>\n
    setImmediate()\u65b9\u6cd5\u7528\u6765\u628a\u4e00\u4e9b\u9700\u8981\u957f\u65f6\u95f4\u8fd0\u884c\u7684\u64cd\u4f5c\u653e\u5728\u4e00\u4e2a\u56de\u8c03\u51fd\u6570\u91cc\uff0c\u5728\u6d4f\u89c8\u5668\u5b8c\u6210\u540e\u9762\u7684\u5176\u4ed6\u8bed\u53e5\u540e\uff0c\u5c31\u7acb\u523b\u6267\u884c\u8fd9\u4e2a\u56de\u8c03\u51fd\u6570\uff0c\u5fc5\u9009\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570func\uff0c\u8868\u793a\u5c06\u8981\u6267\u884c\u7684\u56de\u8c03\u51fd\u6570\uff0c\u5b83\u5e76\u4e0d\u9700\u8981\u65f6\u95f4\u53c2\u6570\u3002<\/p>\n
    \u6ce8\u610f\uff1a\u76ee\u524d\u53ea\u6709IE10\u652f\u6301\u6b64\u65b9\u6cd5\uff0c\u5f53\u7136\uff0c\u5728Nodejs\u4e2d\u4e5f\u53ef\u4ee5\u8c03\u7528\u6b64\u65b9\u6cd5\u3002<\/p>\n
     <\/p>\n
    3\u3001setTimeout\u7684\u4e00\u4e9b\u79d8\u5bc6<\/strong><\/p>\n
    3.1 setTimeout\u4e2d\u56de\u8c03\u51fd\u6570\u7684this<\/p>\n
    \u7531\u4e8esetTimeout() \u65b9\u6cd5\u662f\u6d4f\u89c8\u5668 window \u5bf9\u8c61\u63d0\u4f9b\u7684\uff0c\u56e0\u6b64\u7b2c\u4e00\u4e2a\u53c2\u6570\u51fd\u6570\u4e2d\u7684this\u5176\u5b9e\u662f\u6307\u5411window\u5bf9\u8c61\uff0c\u8fd9\u8ddf\u53d8\u91cf\u7684\u4f5c\u7528\u57df\u6709\u5173\u3002<\/p>\n
    \u770b\u4e2a\u4f8b\u5b50\uff1a<\/p>\n
    var a = 1; \r\nvar obj = { \r\n a: 2, \r\n test: function() { \r\n setTimeout(function(){ \r\n console.log(this.a); \r\n }, 0); \r\n } \r\n}; \r\nobj.test(); \/\/ 1<\/pre>\n
    \u4e0d\u8fc7\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4f7f\u7528bind()\u65b9\u6cd5\u6765\u6539\u53d8setTimeout\u56de\u8c03\u51fd\u6570\u91cc\u7684this<\/p>\n
    var a = 1; \r\nvar obj = { \r\n a: 2, \r\n test: function() { \r\n setTimeout(function(){ \r\n console.log(this.a); \r\n }.bind(this), 0); \r\n } \r\n}; \r\nobj.test(); \/\/ 2<\/pre>\n
    3.2 setTimeout\u4e0d\u6b62\u4e24\u4e2a\u53c2\u6570<\/p>\n
    \u6211\u4eec\u90fd\u77e5\u9053\uff0csetTimeout\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u662f\u8981\u6267\u884c\u7684\u56de\u8c03\u51fd\u6570\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u662f\u5ef6\u8fdf\u65f6\u95f4\uff08\u5982\u679c\u7701\u7565\uff0c\u4f1a\u7531\u6d4f\u89c8\u5668\u81ea\u52a8\u8bbe\u7f6e\u3002\u5728IE\uff0cFireFox\u4e2d\uff0c\u7b2c\u4e00\u6b21\u914d\u53ef\u80fd\u7ed9\u4e2a\u5f88\u5927\u7684\u6570\u5b57\uff0c100ms\u4e0a\u4e0b\uff0c\u5f80\u540e\u4f1a\u7f29\u5c0f\u5230\u6700\u5c0f\u65f6\u95f4\u95f4\u9694\uff0cSafari\uff0cchrome\uff0copera\u5219\u591a\u4e3a10ms\u4e0a\u4e0b\u3002\uff09<\/p>\n
    \u5176\u5b9e\uff0csetTimeout\u53ef\u4ee5\u4f20\u5165\u7b2c\u4e09\u4e2a\u53c2\u6570\u3001\u7b2c\u56db\u4e2a\u53c2\u6570\u2026.\uff0c\u5b83\u4eec\u8868\u793a\u795e\u9a6c\u5462\uff1f\u5176\u5b9e\u662f\u7528\u6765\u8868\u793a\u7b2c\u4e00\u4e2a\u53c2\u6570\uff08\u56de\u8c03\u51fd\u6570\uff09\u4f20\u5165\u7684\u53c2\u6570\u3002<\/p>\n
    setTimeout(function(a, b){ \r\n console.log(a); \/\/ 3\r\n console.log(b); \/\/ 4\r\n},0, 3, 4);<\/pre>\n
     <\/p>\n
    http:\/\/mp.weixin.qq.com\/s\/iyMgSw9DFTWkOmxzEiYRZQ\u00a0<\/a><\/p>\n
     <\/p>\n
     <\/p>\n","protected":false},"excerpt":{"rendered":"
    \u63cf\u8ff0\uff1a\u8ba1\u65f6\u5668setTimeout\u662f\u6211\u4eec\u7ecf\u5e38\u4f1a\u7528\u5230\u7684\uff0c\u5b83\u7528\u4e8e\u5728\u6307\u5b9a\u7684\u6beb\u79d2\u6570\u540e\u8c03\u7528\u51fd\u6570\u6216\u8ba1\u7b97\u8868\u8fbe\u5f0f\u3002 \u8bed\u6cd5\uff1aset […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26,11],"tags":[],"class_list":["post-5646","post","type-post","status-publish","format-standard","hentry","category-javascript","category-11"],"_links":{"self":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/5646","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=5646"}],"version-history":[{"count":0,"href":"https:\/\/sdeno.com\/index.php?rest_route=\/wp\/v2\/posts\/5646\/revisions"}],"wp:attachment":[{"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5646"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5646"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sdeno.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5646"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}