{"id":1383,"date":"2024-06-02T22:32:44","date_gmt":"2024-06-02T22:32:44","guid":{"rendered":""},"modified":"2024-06-05T03:10:11","modified_gmt":"2024-06-04T19:10:11","slug":"javascript%e6%b7%b1%e5%85%a5%e4%b9%8bcall%e5%92%8capply%e7%9a%84%e6%a8%a1%e6%8b%9f%e5%ae%9e%e7%8e%b0","status":"publish","type":"post","link":"https:\/\/www.lccc.top\/?p=1383","title":{"rendered":"JavaScript\u6df1\u5165\u4e4bcall\u548capply\u7684\u6a21\u62df\u5b9e\u73b0"},"content":{"rendered":"\n

call<\/h2>\n

\u4e00\u53e5\u8bdd\u4ecb\u7ecd call\uff1a<\/p>\n

\n

call() \u65b9\u6cd5\u5728\u4f7f\u7528\u4e00\u4e2a\u6307\u5b9a\u7684 this \u503c\u548c\u82e5\u5e72\u4e2a\u6307\u5b9a\u7684\u53c2\u6570\u503c\u7684\u524d\u63d0\u4e0b\u8c03\u7528\u67d0\u4e2a\u51fd\u6570\u6216\u65b9\u6cd5\u3002<\/p>\n<\/blockquote>\n

\u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n

<\/p>\n
var<\/span> foo<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>;<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call<\/span>(<\/span>foo<\/span>)<\/span>;<\/span> \/\/ 1<\/span><\/pre>\n<\/div>\n
\u6ce8\u610f\u4e24\u70b9\uff1a<\/p>\n
    \n
  1. call \u6539\u53d8\u4e86 this \u7684\u6307\u5411\uff0c\u6307\u5411\u5230 foo<\/li>\n
  2. bar \u51fd\u6570\u6267\u884c\u4e86<\/li>\n<\/ol>\n
    \u6a21\u62df\u5b9e\u73b0\u7b2c\u4e00\u6b65<\/h2>\n
    \u90a3\u4e48\u6211\u4eec\u8be5\u600e\u4e48\u6a21\u62df\u5b9e\u73b0\u8fd9\u4e24\u4e2a\u6548\u679c\u5462\uff1f<\/p>\n
    \u8bd5\u60f3\u5f53\u8c03\u7528 call \u7684\u65f6\u5019\uff0c\u628a foo \u5bf9\u8c61\u6539\u9020\u6210\u5982\u4e0b\uff1a<\/p>\n
    <\/p>\n
    var<\/span> foo<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>,<\/span>\n    bar<\/span>: function<\/span>(<\/span>)<\/span> {<\/span>\n        console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>\n    }<\/span>\n}<\/span>;<\/span>\n\nfoo<\/span>.<\/span>bar<\/span>(<\/span>)<\/span>;<\/span> \/\/ 1<\/span><\/pre>\n<\/div>\n
    \u8fd9\u4e2a\u65f6\u5019 this \u5c31\u6307\u5411\u4e86 foo\uff0c\u662f\u4e0d\u662f\u5f88\u7b80\u5355\u5462\uff1f<\/p>\n
    \u4f46\u662f\u8fd9\u6837\u5374\u7ed9 foo \u5bf9\u8c61\u672c\u8eab\u6dfb\u52a0\u4e86\u4e00\u4e2a\u5c5e\u6027\uff0c\u8fd9\u53ef\u4e0d\u884c\u5450\uff01<\/p>\n
    \u4e0d\u8fc7\u4e5f\u4e0d\u7528\u62c5\u5fc3\uff0c\u6211\u4eec\u7528 delete \u518d\u5220\u9664\u5b83\u4e0d\u5c31\u597d\u4e86~<\/p>\n
    \u6240\u4ee5\u6211\u4eec\u6a21\u62df\u7684\u6b65\u9aa4\u53ef\u4ee5\u5206\u4e3a\uff1a<\/p>\n
      \n
    1. \u5c06\u51fd\u6570\u8bbe\u4e3a\u5bf9\u8c61\u7684\u5c5e\u6027<\/li>\n
    2. \u6267\u884c\u8be5\u51fd\u6570<\/li>\n
    3. \u5220\u9664\u8be5\u51fd\u6570<\/li>\n<\/ol>\n
      \u4ee5\u4e0a\u4e2a\u4f8b\u5b50\u4e3a\u4f8b\uff0c\u5c31\u662f\uff1a<\/p>\n
      <\/p>\n
      \/\/ \u7b2c\u4e00\u6b65<\/span>\nfoo<\/span>.<\/span>fn<\/span> =<\/span> bar<\/span>\n\/\/ \u7b2c\u4e8c\u6b65<\/span>\nfoo<\/span>.<\/span>fn<\/span>(<\/span>)<\/span>\n\/\/ \u7b2c\u4e09\u6b65<\/span>\ndelete<\/span> foo<\/span>.<\/span>fn<\/span><\/pre>\n<\/div>\n
      fn \u662f\u5bf9\u8c61\u7684\u5c5e\u6027\u540d\uff0c\u53cd\u6b63\u6700\u540e\u4e5f\u8981\u5220\u9664\u5b83\uff0c\u6240\u4ee5\u8d77\u6210\u4ec0\u4e48\u90fd\u65e0\u6240\u8c13\u3002<\/p>\n
      \u6839\u636e\u8fd9\u4e2a\u601d\u8def\uff0c\u6211\u4eec\u53ef\u4ee5\u5c1d\u8bd5\u7740\u53bb\u5199\u7b2c\u4e00\u7248\u7684 call2<\/strong> \u51fd\u6570\uff1a<\/p>\n
      <\/p>\n
      \/\/ \u7b2c\u4e00\u7248<\/span>\nFunction<\/span>.<\/span>prototype<\/span>.<\/span>call2<\/span> =<\/span> function<\/span>(<\/span>context<\/span>)<\/span> {<\/span>\n    \/\/ \u9996\u5148\u8981\u83b7\u53d6\u8c03\u7528call\u7684\u51fd\u6570\uff0c\u7528this\u53ef\u4ee5\u83b7\u53d6<\/span>\n    context<\/span>.<\/span>fn<\/span> =<\/span> this<\/span>;<\/span>\n    context<\/span>.<\/span>fn<\/span>(<\/span>)<\/span>;<\/span>\n    delete<\/span> context<\/span>.<\/span>fn<\/span>;<\/span>\n}<\/span>\n\n\/\/ \u6d4b\u8bd5\u4e00\u4e0b<\/span>\nvar<\/span> foo<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>;<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call2<\/span>(<\/span>foo<\/span>)<\/span>;<\/span> \/\/ 1<\/span><\/pre>\n<\/div>\n
      \u6b63\u597d\u53ef\u4ee5\u6253\u5370 1 \u54ce\uff01\u662f\u4e0d\u662f\u5f88\u5f00\u5fc3\uff01(\uff5e\uffe3\u25bd\uffe3)\uff5e<\/p>\n
      \u6a21\u62df\u5b9e\u73b0\u7b2c\u4e8c\u6b65<\/h2>\n
      \u6700\u4e00\u5f00\u59cb\u4e5f\u8bb2\u4e86\uff0ccall \u51fd\u6570\u8fd8\u80fd\u7ed9\u5b9a\u53c2\u6570\u6267\u884c\u51fd\u6570\u3002\u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n
      <\/p>\n
      var<\/span> foo<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>;<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>name<\/span>,<\/span> age<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>name<\/span>)<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>age<\/span>)<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call<\/span>(<\/span>foo<\/span>,<\/span> 'kevin'<\/span>,<\/span> 18<\/span>)<\/span>;<\/span>\n\/\/ kevin<\/span>\n\/\/ 18<\/span>\n\/\/ 1<\/span><\/pre>\n<\/div>\n
      \u6ce8\u610f\uff1a\u4f20\u5165\u7684\u53c2\u6570\u5e76\u4e0d\u786e\u5b9a\uff0c\u8fd9\u53ef\u548b\u529e\uff1f<\/p>\n
      \u4e0d\u6025\uff0c\u6211\u4eec\u53ef\u4ee5\u4ece Arguments \u5bf9\u8c61\u4e2d\u53d6\u503c\uff0c\u53d6\u51fa\u7b2c\u4e8c\u4e2a\u5230\u6700\u540e\u4e00\u4e2a\u53c2\u6570\uff0c\u7136\u540e\u653e\u5230\u4e00\u4e2a\u6570\u7ec4\u91cc\u3002<\/p>\n
      \u6bd4\u5982\u8fd9\u6837\uff1a<\/p>\n
      <\/p>\n
      \/\/ \u4ee5\u4e0a\u4e2a\u4f8b\u5b50\u4e3a\u4f8b\uff0c\u6b64\u65f6\u7684arguments\u4e3a\uff1a<\/span>\n\/\/ arguments = {<\/span>\n\/\/      0: foo,<\/span>\n\/\/      1: 'kevin',<\/span>\n\/\/      2: 18,<\/span>\n\/\/      length: 3<\/span>\n\/\/ }<\/span>\n\/\/ \u56e0\u4e3aarguments\u662f\u7c7b\u6570\u7ec4\u5bf9\u8c61\uff0c\u6240\u4ee5\u53ef\u4ee5\u7528for\u5faa\u73af<\/span>\nvar<\/span> args<\/span> =<\/span> [<\/span>]<\/span>;<\/span>\nfor<\/span>(<\/span>var<\/span> i<\/span> =<\/span> 1<\/span>,<\/span> len<\/span> =<\/span> arguments<\/span>.<\/span>length<\/span>;<\/span> i<\/span> <<\/span> len<\/span>;<\/span> i<\/span>++<\/span>)<\/span> {<\/span>\n    args<\/span>.<\/span>push<\/span>(<\/span>'arguments['<\/span> +<\/span> i<\/span> +<\/span> ']'<\/span>)<\/span>;<\/span>\n}<\/span>\n\n\/\/ \u6267\u884c\u540e args\u4e3a [\"arguments[1]\", \"arguments[2]\", \"arguments[3]\"]<\/span><\/pre>\n<\/div>\n
      \u4e0d\u5b9a\u957f\u7684\u53c2\u6570\u95ee\u9898\u89e3\u51b3\u4e86\uff0c\u6211\u4eec\u63a5\u7740\u8981\u628a\u8fd9\u4e2a\u53c2\u6570\u6570\u7ec4\u653e\u5230\u8981\u6267\u884c\u7684\u51fd\u6570\u7684\u53c2\u6570\u91cc\u9762\u53bb\u3002<\/p>\n
      <\/p>\n
      \/\/ \u5c06\u6570\u7ec4\u91cc\u7684\u5143\u7d20\u4f5c\u4e3a\u591a\u4e2a\u53c2\u6570\u653e\u8fdb\u51fd\u6570\u7684\u5f62\u53c2\u91cc<\/span>\ncontext<\/span>.<\/span>fn<\/span>(<\/span>args<\/span>.<\/span>join<\/span>(<\/span>','<\/span>)<\/span>)<\/span>\n\/\/ (O_o)??<\/span>\n\/\/ \u8fd9\u4e2a\u65b9\u6cd5\u80af\u5b9a\u662f\u4e0d\u884c\u7684\u5566\uff01\uff01\uff01<\/span><\/pre>\n<\/div>\n
      \u4e5f\u8bb8\u6709\u4eba\u60f3\u5230\u7528 ES6 \u7684\u65b9\u6cd5\uff0c\u4e0d\u8fc7 call \u662f ES3 \u7684\u65b9\u6cd5\uff0c\u6211\u4eec\u4e3a\u4e86\u6a21\u62df\u5b9e\u73b0\u4e00\u4e2a ES3 \u7684\u65b9\u6cd5\uff0c\u8981\u7528\u5230ES6\u7684\u65b9\u6cd5\uff0c\u597d\u50cf\u2026\u2026\uff0c\u55ef\uff0c\u4e5f\u53ef\u4ee5\u5566\u3002\u4f46\u662f\u6211\u4eec\u8fd9\u6b21\u7528 eval \u65b9\u6cd5\u62fc\u6210\u4e00\u4e2a\u51fd\u6570\uff0c\u7c7b\u4f3c\u4e8e\u8fd9\u6837\uff1a<\/p>\n
      \n
      eval<\/span>(<\/span>'context.fn('<\/span> +<\/span> args<\/span> +<\/span>')'<\/span>)<\/span><\/pre>\n<\/div>\n
      \u8fd9\u91cc args \u4f1a\u81ea\u52a8\u8c03\u7528 Array.toString() \u8fd9\u4e2a\u65b9\u6cd5\u3002<\/p>\n
      \u6240\u4ee5\u6211\u4eec\u7684\u7b2c\u4e8c\u7248\u514b\u670d\u4e86\u4e24\u4e2a\u5927\u95ee\u9898\uff0c\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n
      <\/p>\n
      \/\/ \u7b2c\u4e8c\u7248<\/span>\nFunction<\/span>.<\/span>prototype<\/span>.<\/span>call2<\/span> =<\/span> function<\/span>(<\/span>context<\/span>)<\/span> {<\/span>\n    context<\/span>.<\/span>fn<\/span> =<\/span> this<\/span>;<\/span>\n    var<\/span> args<\/span> =<\/span> [<\/span>]<\/span>;<\/span>\n    for<\/span>(<\/span>var<\/span> i<\/span> =<\/span> 1<\/span>,<\/span> len<\/span> =<\/span> arguments<\/span>.<\/span>length<\/span>;<\/span> i<\/span> <<\/span> len<\/span>;<\/span> i<\/span>++<\/span>)<\/span> {<\/span>\n        args<\/span>.<\/span>push<\/span>(<\/span>'arguments['<\/span> +<\/span> i<\/span> +<\/span> ']'<\/span>)<\/span>;<\/span>\n    }<\/span>\n    eval<\/span>(<\/span>'context.fn('<\/span> +<\/span> args<\/span> +<\/span>')'<\/span>)<\/span>;<\/span>\n    delete<\/span> context<\/span>.<\/span>fn<\/span>;<\/span>\n}<\/span>\n\n\/\/ \u6d4b\u8bd5\u4e00\u4e0b<\/span>\nvar<\/span> foo<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>;<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>name<\/span>,<\/span> age<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>name<\/span>)<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>age<\/span>)<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call2<\/span>(<\/span>foo<\/span>,<\/span> 'kevin'<\/span>,<\/span> 18<\/span>)<\/span>;<\/span> \n\/\/ kevin<\/span>\n\/\/ 18<\/span>\n\/\/ 1<\/span><\/pre>\n<\/div>\n
      (\u0e51\u2022\u0300\u3142\u2022\u0301)\u0648\u2727<\/p>\n
      \u6a21\u62df\u5b9e\u73b0\u7b2c\u4e09\u6b65<\/h2>\n
      \u6a21\u62df\u4ee3\u7801\u5df2\u7ecf\u5b8c\u6210 80%\uff0c\u8fd8\u6709\u4e24\u4e2a\u5c0f\u70b9\u8981\u6ce8\u610f\uff1a<\/p>\n
      1.this \u53c2\u6570\u53ef\u4ee5\u4f20 null\uff0c\u5f53\u4e3a null \u7684\u65f6\u5019\uff0c\u89c6\u4e3a\u6307\u5411 window<\/strong><\/p>\n
      \u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n
      <\/p>\n
      var<\/span> value<\/span> =<\/span> 1<\/span>;<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call<\/span>(<\/span>null<\/span>)<\/span>;<\/span> \/\/ 1<\/span><\/pre>\n<\/div>\n
      \u867d\u7136\u8fd9\u4e2a\u4f8b\u5b50\u672c\u8eab\u4e0d\u4f7f\u7528 call\uff0c\u7ed3\u679c\u4f9d\u7136\u4e00\u6837\u3002<\/p>\n
      2.\u51fd\u6570\u662f\u53ef\u4ee5\u6709\u8fd4\u56de\u503c\u7684\uff01<\/strong><\/p>\n
      \u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n
      <\/p>\n
      var<\/span> obj<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>name<\/span>,<\/span> age<\/span>)<\/span> {<\/span>\n    return<\/span> {<\/span>\n        value<\/span>: this<\/span>.<\/span>value<\/span>,<\/span>\n        name<\/span>: name<\/span>,<\/span>\n        age<\/span>: age<\/span>\n    }<\/span>\n}<\/span>\n\nconsole<\/span>.<\/span>log<\/span>(<\/span>bar<\/span>.<\/span>call<\/span>(<\/span>obj<\/span>,<\/span> 'kevin'<\/span>,<\/span> 18<\/span>)<\/span>)<\/span>;<\/span>\n\/\/ Object {<\/span>\n\/\/    value: 1,<\/span>\n\/\/    name: 'kevin',<\/span>\n\/\/    age: 18<\/span>\n\/\/ }<\/span><\/pre>\n<\/div>\n
      \u4e0d\u8fc7\u90fd\u5f88\u597d\u89e3\u51b3\uff0c\u8ba9\u6211\u4eec\u76f4\u63a5\u770b\u7b2c\u4e09\u7248\u4e5f\u5c31\u662f\u6700\u540e\u4e00\u7248\u7684\u4ee3\u7801\uff1a<\/p>\n
      <\/p>\n
      \/\/ \u7b2c\u4e09\u7248<\/span>\nFunction<\/span>.<\/span>prototype<\/span>.<\/span>call2<\/span> =<\/span> function<\/span> (<\/span>context<\/span>)<\/span> {<\/span>\n    var<\/span> context<\/span> =<\/span> context<\/span> ||<\/span> window<\/span>;<\/span>\n    context<\/span>.<\/span>fn<\/span> =<\/span> this<\/span>;<\/span>\n\n    var<\/span> args<\/span> =<\/span> [<\/span>]<\/span>;<\/span>\n    for<\/span>(<\/span>var<\/span> i<\/span> =<\/span> 1<\/span>,<\/span> len<\/span> =<\/span> arguments<\/span>.<\/span>length<\/span>;<\/span> i<\/span> <<\/span> len<\/span>;<\/span> i<\/span>++<\/span>)<\/span> {<\/span>\n        args<\/span>.<\/span>push<\/span>(<\/span>'arguments['<\/span> +<\/span> i<\/span> +<\/span> ']'<\/span>)<\/span>;<\/span>\n    }<\/span>\n\n    var<\/span> result<\/span> =<\/span> eval<\/span>(<\/span>'context.fn('<\/span> +<\/span> args<\/span> +<\/span>')'<\/span>)<\/span>;<\/span>\n\n    delete<\/span> context<\/span>.<\/span>fn<\/span>\n    return<\/span> result<\/span>;<\/span>\n}<\/span>\n\n\/\/ \u6d4b\u8bd5\u4e00\u4e0b<\/span>\nvar<\/span> value<\/span> =<\/span> 2<\/span>;<\/span>\n\nvar<\/span> obj<\/span> =<\/span> {<\/span>\n    value<\/span>: 1<\/span>\n}<\/span>\n\nfunction<\/span> bar<\/span>(<\/span>name<\/span>,<\/span> age<\/span>)<\/span> {<\/span>\n    console<\/span>.<\/span>log<\/span>(<\/span>this<\/span>.<\/span>value<\/span>)<\/span>;<\/span>\n    return<\/span> {<\/span>\n        value<\/span>: this<\/span>.<\/span>value<\/span>,<\/span>\n        name<\/span>: name<\/span>,<\/span>\n        age<\/span>: age<\/span>\n    }<\/span>\n}<\/span>\n\nbar<\/span>.<\/span>call2<\/span>(<\/span>null<\/span>)<\/span>;<\/span> \/\/ 2<\/span>\n\nconsole<\/span>.<\/span>log<\/span>(<\/span>bar<\/span>.<\/span>call2<\/span>(<\/span>obj<\/span>,<\/span> 'kevin'<\/span>,<\/span> 18<\/span>)<\/span>)<\/span>;<\/span>\n\/\/ 1<\/span>\n\/\/ Object {<\/span>\n\/\/    value: 1,<\/span>\n\/\/    name: 'kevin',<\/span>\n\/\/    age: 18<\/span>\n\/\/ }<\/span><\/pre>\n<\/div>\n
      \u5230\u6b64\uff0c\u6211\u4eec\u5b8c\u6210\u4e86 call \u7684\u6a21\u62df\u5b9e\u73b0\uff0c\u7ed9\u81ea\u5df1\u4e00\u4e2a\u8d5e \uff42\uff08\uffe3\u25bd\uffe3\uff09\uff44<\/p>\n
      apply\u7684\u6a21\u62df\u5b9e\u73b0<\/h2>\n
      apply \u7684\u5b9e\u73b0\u8ddf call \u7c7b\u4f3c\uff0c\u5728\u8fd9\u91cc\u76f4\u63a5\u7ed9\u4ee3\u7801\uff0c\u4ee3\u7801\u6765\u81ea\u4e8e\u77e5\u4e4e @\u90d1\u822a\u7684\u5b9e\u73b0\uff1a<\/p>\n
      <\/p>\n
      Function<\/span>.<\/span>prototype<\/span>.<\/span>apply<\/span> =<\/span> function<\/span> (<\/span>context<\/span>,<\/span> arr<\/span>)<\/span> {<\/span>\n    var<\/span> context<\/span> =<\/span> Object<\/span>(<\/span>context<\/span>)<\/span> ||<\/span> window<\/span>;<\/span>\n    context<\/span>.<\/span>fn<\/span> =<\/span> this<\/span>;<\/span>\n\n    var<\/span> result<\/span>;<\/span>\n    if<\/span> (<\/span>!<\/span>arr<\/span>)<\/span> {<\/span>\n        result<\/span> =<\/span> context<\/span>.<\/span>fn<\/span>(<\/span>)<\/span>;<\/span>\n    }<\/span>\n    else<\/span> {<\/span>\n        var<\/span> args<\/span> =<\/span> [<\/span>]<\/span>;<\/span>\n        for<\/span> (<\/span>var<\/span> i<\/span> =<\/span> 0<\/span>,<\/span> len<\/span> =<\/span> arr<\/span>.<\/span>length<\/span>;<\/span> i<\/span> <<\/span> len<\/span>;<\/span> i<\/span>++<\/span>)<\/span> {<\/span>\n            args<\/span>.<\/span>push<\/span>(<\/span>'arr['<\/span> +<\/span> i<\/span> +<\/span> ']'<\/span>)<\/span>;<\/span>\n        }<\/span>\n        result<\/span> =<\/span> eval<\/span>(<\/span>'context.fn('<\/span> +<\/span> args<\/span> +<\/span> ')'<\/span>)<\/span>\n    }<\/span>\n\n    delete<\/span> context<\/span>.<\/span>fn<\/span>\n    return<\/span> result<\/span>;<\/span>\n}<\/span><\/pre>\n<\/div>\n
      \u4e0b\u4e00\u7bc7\u6587\u7ae0<\/h2>\n
      JavaScript\u6df1\u5165\u4e4bbind\u7684\u6a21\u62df\u5b9e\u73b0<\/a><\/p>\n
      \u91cd\u8981\u53c2\u8003<\/h2>\n
      \u77e5\u4e4e\u95ee\u9898 \u4e0d\u80fd\u4f7f\u7528call\u3001apply\u3001bind\uff0c\u5982\u4f55\u7528 js \u5b9e\u73b0 call \u6216\u8005 apply \u7684\u529f\u80fd\uff1f<\/a><\/p>\n
      \u6df1\u5165\u7cfb\u5217<\/h2>\n
      JavaScript\u6df1\u5165\u7cfb\u5217\u76ee\u5f55\u5730\u5740\uff1ahttps:\/\/github.com\/mqyqingfeng\/Blog<\/a>\u3002<\/p>\n
      JavaScript\u6df1\u5165\u7cfb\u5217\u9884\u8ba1\u5199\u5341\u4e94\u7bc7\u5de6\u53f3\uff0c\u65e8\u5728\u5e2e\u5927\u5bb6\u634b\u987aJavaScript\u5e95\u5c42\u77e5\u8bc6\uff0c\u91cd\u70b9\u8bb2\u89e3\u5982\u539f\u578b\u3001\u4f5c\u7528\u57df\u3001\u6267\u884c\u4e0a\u4e0b\u6587\u3001\u53d8\u91cf\u5bf9\u8c61\u3001this\u3001\u95ed\u5305\u3001\u6309\u503c\u4f20\u9012\u3001call\u3001apply\u3001bind\u3001new\u3001\u7ee7\u627f\u7b49\u96be\u70b9\u6982\u5ff5\u3002<\/p>\n
      \u5982\u679c\u6709\u9519\u8bef\u6216\u8005\u4e0d\u4e25\u8c28\u7684\u5730\u65b9\uff0c\u8bf7\u52a1\u5fc5\u7ed9\u4e88\u6307\u6b63\uff0c\u5341\u5206\u611f\u8c22\u3002\u5982\u679c\u559c\u6b22\u6216\u8005\u6709\u6240\u542f\u53d1\uff0c\u6b22\u8fcestar\uff0c\u5bf9\u4f5c\u8005\u4e5f\u662f\u4e00\u79cd\u9f13\u52b1\u3002<\/p>\n<\/td>\n
      \u6587\u7ae0\u8f6c\u8f7d\u81eahttps:\/\/github.com\/mqyqingfeng\/Blog\/issues\/11<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
      call \u4e00\u53e5\u8bdd\u4ecb\u7ecd call\uff1a call() \u65b9\u6cd5\u5728\u4f7f\u7528\u4e00\u4e2a\u6307\u5b9a\u7684 this \u503c\u548c\u82e5\u5e72\u4e2a\u6307\u5b9a\u7684\u53c2\u6570\u503c\u7684\u524d\u63d0\u4e0b\u8c03\u7528\u67d0\u4e2a\u51fd\u6570\u6216\u65b9\u6cd5\u3002 \u4e3e\u4e2a\u4f8b\u5b50\uff1a var foo …<\/p>\n
       Read More  Read More<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1383","post","type-post","status-publish","format-standard","hentry","category-learn"],"_links":{"self":[{"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/posts\/1383"}],"collection":[{"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lccc.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1383"}],"version-history":[{"count":1,"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/posts\/1383\/revisions"}],"predecessor-version":[{"id":1498,"href":"https:\/\/www.lccc.top\/index.php?rest_route=\/wp\/v2\/posts\/1383\/revisions\/1498"}],"wp:attachment":[{"href":"https:\/\/www.lccc.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1383"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lccc.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1383"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lccc.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1383"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}