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    537. 

  537. 

  538.         
    539. 

  539.         </a>
    540. 

  540.         
    541. 

  541. 

  542.         
    543. 

  543.     
    544. 

  544.         
    545. 

  545.         <a href="../../ubuntu/instruction.html" class="list-group-item ">
    546. 

  546.         
    547. 

  547. 

  548.             
    549. 

  549. 

  550.             
    551. 

  551. 

  552.             常用指令
    553. 

  553. 

  554.         
    555. 

  555.         </a>
    556. 

  556.         
    557. 

  557. 

  558.         
    559. 

  559.     
    560. 

  560.         
    561. 

  561.         <a href="../../ubuntu/software/" class="list-group-item ">
    562. 

  562.         
    563. 

  563. 

  564.             
    565. 

  565. 

  566.             
    567. 

  567. 

  568.             常用软件安装
    569. 

  569. 

  570.         
    571. 

  571.         </a>
    572. 

  572.         
    573. 

  573. 

  574.         
    575. 

  575.     
    576. 

  576. 

  577.         </div>
    578. 

  578.     </div>
    579. 

  579.     
    580. 

  580.     <div class="panel panel-default">
    581. 

  581.         
    582. 

  582.         <div class="panel-heading">
    583. 

  583.             <h3 class="panel-title">GIT</h3>
    584. 

  584.         </div>
    585. 

  585.         
    586. 

  586. 

  587.         <div class="list-group">
    588. 

  588.             
    589. 

  589.     
    590. 

  590.         
    591. 

  591.         <a href="../../git/git.html" class="list-group-item ">
    592. 

  592.         
    593. 

  593. 

  594.             
    595. 

  595. 

  596.             
    597. 

  597. 

  598.             git 命令
    599. 

  599. 

  600.         
    601. 

  601.         </a>
    602. 

  602.         
    603. 

  603. 

  604.         
    605. 

  605.     
    606. 

  606.         
    607. 

  607.         <a href="../../git/push.html" class="list-group-item ">
    608. 

  608.         
    609. 

  609. 

  610.             
    611. 

  611. 

  612.             
    613. 

  613. 

  614.             git~push
    615. 

  615. 

  616.         
    617. 

  617.         </a>
    618. 

  618.         
    619. 

  619. 

  620.         
    621. 

  621.     
    622. 

  622.         
    623. 

  623.         <a href="../../git/faq.html" class="list-group-item ">
    624. 

  624.         
    625. 

  625. 

  626.             
    627. 

  627. 

  628.             
    629. 

  629. 

  630.             git~F.A.Q
    631. 

  631. 

  632.         
    633. 

  633.         </a>
    634. 

  634.         
    635. 

  635. 

  636.         
    637. 

  637.     
    638. 

  638. 

  639.         </div>
    640. 

  640.     </div>
    641. 

  641.     
    642. 

  642.     <div class="panel panel-default">
    643. 

  643.         
    644. 

  644.         <div class="panel-heading">
    645. 

  645.             <h3 class="panel-title">NODE&NPM</h3>
    646. 

  646.         </div>
    647. 

  647.         
    648. 

  648. 

  649.         <div class="list-group">
    650. 

  650.             
    651. 

  651.     
    652. 

  652.         
    653. 

  653.         <a href="../../node/0.html" class="list-group-item ">
    654. 

  654.         
    655. 

  655. 

  656.             
    657. 

  657. 

  658.             
    659. 

  659.             <i class="octicon octicon-chevron-right"></i>
    660. 

  660.             
    661. 

  661. 

  662.             node
    663. 

  663. 

  664.         
    665. 

  665.         </a>
    666. 

  666.         
    667. 

  667. 

  668.         
    669. 

  669.     
    670. 

  670.         
    671. 

  671.         <a href="../../node/npm/0.html" class="list-group-item ">
    672. 

  672.         
    673. 

  673. 

  674.             
    675. 

  675. 

  676.             
    677. 

  677. 

  678.             npm
    679. 

  679. 

  680.         
    681. 

  681.         </a>
    682. 

  682.         
    683. 

  683. 

  684.         
    685. 

  685.     
    686. 

  686. 

  687.         </div>
    688. 

  688.     </div>
    689. 

  689.     
    690. 

  690.     <div class="panel panel-default">
    691. 

  691.         
    692. 

  692. 

  693.         <div class="list-group">
    694. 

  694.             
    695. 

  695.     
    696. 

  696.         
    697. 

  697.         <a href="../../other/faq.html" class="list-group-item ">
    698. 

  698.         
    699. 

  699. 

  700.             
    701. 

  701. 

  702.             
    703. 

  703. 

  704.             FAQ
    705. 

  705. 

  706.         
    707. 

  707.         </a>
    708. 

  708.         
    709. 

  709. 

  710.         
    711. 

  711.     
    712. 

  712.         
    713. 

  713.         <a href="../../other/examples.html" class="list-group-item ">
    714. 

  714.         
    715. 

  715. 

  716.             
    717. 

  717. 

  718.             
    719. 

  719. 

  720.             Examples
    721. 

  721. 

  722.         
    723. 

  723.         </a>
    724. 

  724.         
    725. 

  725. 

  726.         
    727. 

  727.     
    728. 

  728. 

  729.         </div>
    730. 

  730.     </div>
    731. 

  731.     
    732. 

  732. 

  733. 

  734. 

  735.                     </div>
    736. 

  736.                     <div class="col-md-9">
    737. 

  737.                         
    738. 

  738. <div id="book-search-results">
    739. 

  739.     <div class="search-noresults">
    740. 

  740.     
    741. 

  741.                             
    742. 

  742. 

  743.                             <div class="gb-markdown book-page-inner">
    744. 

  744.                                 <h1 id="&#x5199;&#x7ED9;&#x521D;&#x7EA7;js&#x7A0B;&#x5E8F;&#x5458;&#x7684;javascript&#x95ED;&#x5305;&#x8BD1;">&#x5199;&#x7ED9;&#x521D;&#x7EA7;JS&#x7A0B;&#x5E8F;&#x5458;&#x7684;JavaScript&#x95ED;&#x5305;(&#x8BD1;)</h1>
    745. 

  745. <p><a href="http://web.archive.org/web/20080209105120/http:/blog.morrisjohns.com/javascript_closures_for_dummies" target="_blank">&#x539F;&#x6587;&#x94FE;&#x63A5;</a></p>
    746. 

  746. <h1 id="&#x95ED;&#x5305;&#x4E0D;&#x662F;&#x9B54;&#x672F;">&#x95ED;&#x5305;&#x4E0D;&#x662F;&#x9B54;&#x672F;</h1>
    747. 

  747. <blockquote>
    748. 

  748. <p>&#x8FD9;&#x4E2A;&#x9875;&#x9762;&#x89E3;&#x91CA;&#x4E86;closures&#xFF0C;&#x4EE5;&#x4FBF;&#x7A0B;&#x5E8F;&#x5458;&#x53EF;&#x4EE5;&#x7406;&#x89E3;&#x5B83;&#x4EEC; - &#x4F7F;&#x7528;&#x6709;&#x6548;&#x7684;JavaScript&#x4EE3;&#x7801;&#x3002;&#x5B83;&#x4E0D;&#x662F;&#x7528;&#x4E8E;&#x53E4;&#x8339;&#x6216;&#x529F;&#x80FD;&#x7A0B;&#x5E8F;&#x5458;&#x3002;
    749. 

  749. &#x4E00;&#x65E6;&#x6838;&#x5FC3;&#x6982;&#x5FF5;&#x88AB;&#x89E3;&#x6784;&#xFF0C;&#x95ED;&#x5305;&#x4E0D;&#x96BE;&#x7406;&#x89E3;&#x3002;&#x7136;&#x800C;&#xFF0C;&#x4ED6;&#x4EEC;&#x4E0D;&#x53EF;&#x80FD;&#x901A;&#x8FC7;&#x9605;&#x8BFB;&#x4EFB;&#x4F55;&#x5B66;&#x672F;&#x8BBA;&#x6587;&#x6216;&#x9762;&#x5411;&#x5B66;&#x672F;&#x7684;&#x4FE1;&#x606F;&#x6765;&#x4E86;&#x89E3;&#x4ED6;&#x4EEC;&#xFF01;
    750. 

  750. &#x672C;&#x6587;&#x4E3B;&#x8981;&#x9762;&#x5411;&#x6709;&#x4E3B;&#x6D41;&#x8BED;&#x8A00;&#x7F16;&#x7A0B;&#x7ECF;&#x9A8C;&#x7684;&#x7A0B;&#x5E8F;&#x5458;&#xFF0C;&#x4ED6;&#x4EEC;&#x53EF;&#x4EE5;&#x9605;&#x8BFB;&#x4EE5;&#x4E0B;JavaScript&#x51FD;&#x6570;&#xFF1A;</p>
    751. 

  751. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">sayHello</span>(<span class="hljs-params">name</span>) </span>{
    752. 

  752.   <span class="hljs-keyword">var</span> text = <span class="hljs-string">&apos;Hello &apos;</span> + name;
    753. 

  753.   <span class="hljs-keyword">var</span> say = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(text); }
    754. 

  754.   say();
    755. 

  755. }
    756. 

  756. sayHello(<span class="hljs-string">&apos;Joe&apos;</span>);
    757. 

  757. </code></pre>
    758. 

  758. </blockquote>
    759. 

  759. <h3 id="&#x95ED;&#x5305;&#x7684;&#x5B9E;&#x4F8B;">&#x95ED;&#x5305;&#x7684;&#x5B9E;&#x4F8B;</h3>
    760. 

  760. <blockquote>
    761. 

  761. <p>&#x4E24;&#x53E5;&#x8BDD;&#x6458;&#x8981;&#xFF1A;<br></p>
    762. 

  762. <h5 id="&#xA0;&#xA0;&#xA0;&#xA0;&#x5B83;&#x662F;&#x4E00;&#x4E2A;&#x53EF;&#x4EE5;&#x5F15;&#x7528;&#x5176;&#x8303;&#x56F4;&#x5185;&#x7684;&#x53D8;&#x91CF;&#xFF08;&#x5728;&#x7B2C;&#x4E00;&#x6B21;&#x58F0;&#x660E;&#x65F6;&#xFF09;&#xFF0C;&#x88AB;&#x8D4B;&#x503C;&#x7ED9;&#x53D8;&#x91CF;&#xFF0C;&#x4F5C;&#x4E3A;&#x53C2;&#x6570;&#x4F20;&#x9012;&#x7ED9;&#x51FD;&#x6570;&#x6216;&#x4F5C;&#x4E3A;&#x51FD;&#x6570;&#x7ED3;&#x679C;&#x8FD4;&#x56DE;&#x7684;&#x8868;&#x8FBE;&#x5F0F;&#x3002;">&#xA0;&#xA0;&#xA0;&#xA0;.&#x5B83;&#x662F;&#x4E00;&#x4E2A;&#x53EF;&#x4EE5;&#x5F15;&#x7528;&#x5176;&#x8303;&#x56F4;&#x5185;&#x7684;&#x53D8;&#x91CF;&#xFF08;&#x5728;&#x7B2C;&#x4E00;&#x6B21;&#x58F0;&#x660E;&#x65F6;&#xFF09;&#xFF0C;&#x88AB;&#x8D4B;&#x503C;&#x7ED9;&#x53D8;&#x91CF;&#xFF0C;&#x4F5C;&#x4E3A;&#x53C2;&#x6570;&#x4F20;&#x9012;&#x7ED9;&#x51FD;&#x6570;&#x6216;&#x4F5C;&#x4E3A;&#x51FD;&#x6570;&#x7ED3;&#x679C;&#x8FD4;&#x56DE;&#x7684;&#x8868;&#x8FBE;&#x5F0F;&#x3002;<br></h5>
    763. 

  763. <h5 id="&#xA0;&#xA0;&#xA0;&#xA0;&#x95ED;&#x5305;&#x662F;&#x4E00;&#x4E2A;&#x5806;&#x6808;&#x6846;&#x67B6;&#xFF0C;&#x5F53;&#x51FD;&#x6570;&#x5F00;&#x59CB;&#x6267;&#x884C;&#x65F6;&#x88AB;&#x5206;&#x914D;&#xFF0C;&#x5E76;&#x4E14;&#x5728;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x4E4B;&#x540E;&#x4E0D;&#x88AB;&#x91CA;&#x653E;&#xFF08;&#x5C31;&#x597D;&#x50CF;&#x5806;&#x6808;&#x6846;&#x67B6;&#x5728;&#x5806;&#x4E0A;&#x5206;&#x914D;&#x800C;&#x4E0D;&#x662F;&#x5806;&#x6808;&#xFF01;&#xFF09;&#x3002;">&#xA0;&#xA0;&#xA0;&#xA0;.&#x95ED;&#x5305;&#x662F;&#x4E00;&#x4E2A;&#x5806;&#x6808;&#x6846;&#x67B6;&#xFF0C;&#x5F53;&#x51FD;&#x6570;&#x5F00;&#x59CB;&#x6267;&#x884C;&#x65F6;&#x88AB;&#x5206;&#x914D;&#xFF0C;&#x5E76;&#x4E14;&#x5728;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x4E4B;&#x540E;&#x4E0D;&#x88AB;&#x91CA;&#x653E;&#xFF08;&#x5C31;&#x597D;&#x50CF;&#x201C;&#x5806;&#x6808;&#x6846;&#x67B6;&#x201D;&#x5728;&#x5806;&#x4E0A;&#x5206;&#x914D;&#x800C;&#x4E0D;&#x662F;&#x5806;&#x6808;&#xFF01;&#xFF09;&#x3002;<br></h5>
    764. 

  764. </blockquote>
    765. 

  765. <p>&#x4EE5;&#x4E0B;&#x4EE3;&#x7801;&#x8FD4;&#x56DE;&#x5BF9;&#x51FD;&#x6570;&#x7684;&#x5F15;&#x7528;&#xFF1A;</p>
    766. 

  766. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">sayHello2</span>(<span class="hljs-params">name</span>) </span>{
    767. 

  767.   <span class="hljs-keyword">var</span> text = <span class="hljs-string">&apos;Hello &apos;</span> + name; <span class="hljs-comment">// Local variable</span>
    768. 

  768.   <span class="hljs-keyword">var</span> say = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(text); }
    769. 

  769.   <span class="hljs-keyword">return</span> say;
    770. 

  770. }
    771. 

  771. <span class="hljs-keyword">var</span> say2 = sayHello2(<span class="hljs-string">&apos;Bob&apos;</span>);
    772. 

  772. say2(); <span class="hljs-comment">// logs &quot;Hello Bob&quot;</span>
    773. 

  773. </code></pre>
    774. 

  774. <blockquote>
    775. 

  775. <p>&#x5927;&#x591A;&#x6570;JavaScript&#x7A0B;&#x5E8F;&#x5458;&#x5C06;&#x4F1A;&#x7406;&#x89E3;&#x5728;&#x4E0A;&#x9762;&#x7684;&#x4EE3;&#x7801;&#x4E2D;&#x5982;&#x4F55;&#x5C06;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x7684;&#x5F15;&#x7528;&#x8FD4;&#x56DE;&#x7ED9;&#x4E00;&#x4E2A;&#x53D8;&#x91CF;&#x3002;&#x5982;&#x679C;&#x4F60;&#x6CA1;&#x6709;&#xFF0C;&#x90A3;&#x4E48;&#x4F60;&#x9700;&#x8981;&#x5728;&#x4F60;&#x53EF;&#x4EE5;&#x5B66;&#x4E60;&#x95ED;&#x5305;&#x3002;AC&#x7A0B;&#x5E8F;&#x5458;&#x4F1A;&#x8BA4;&#x4E3A;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x4E00;&#x4E2A;&#x6307;&#x5411;&#x51FD;&#x6570;&#x7684;&#x6307;&#x9488;&#xFF0C;&#x53D8;&#x91CF;sayAlert&#x548C;say2&#x90FD;&#x662F;&#x6307;&#x5411;&#x51FD;&#x6570;&#x7684;&#x6307;&#x9488;&#x3002;</p>
    776. 

  776. <p>&#x5728;&#x6307;&#x5411;&#x51FD;&#x6570;&#x7684;C&#x6307;&#x9488;&#x548C;&#x5BF9;&#x51FD;&#x6570;&#x7684;JavaScript&#x5F15;&#x7528;&#x4E4B;&#x95F4;&#x5B58;&#x5728;&#x5173;&#x952E;&#x7684;&#x533A;&#x522B;&#x3002;&#x5728;JavaScript&#x4E2D;&#xFF0C;&#x60A8;&#x53EF;&#x4EE5;&#x5C06;&#x51FD;&#x6570;&#x5F15;&#x7528;&#x53D8;&#x91CF;&#x770B;&#x4F5C;&#x5177;&#x6709;&#x6307;&#x5411;&#x51FD;&#x6570;&#x7684;&#x6307;&#x9488; &#x4EE5;&#x53CA;&#x6307;&#x5411;&#x95ED;&#x5305;&#x7684;&#x9690;&#x85CF;&#x6307;&#x9488;&#x3002;</p>
    777. 

  777. <p>&#x4E0A;&#x9762;&#x7684;&#x4EE3;&#x7801;&#x6709;&#x4E00;&#x4E2A;&#x95ED;&#x5305;&#xFF0C;&#x56E0;&#x4E3A;&#x533F;&#x540D;&#x51FD;&#x6570;function&#xFF08;&#xFF09;{alert&#xFF08;text&#xFF09;; } &#x5728;&#x53E6;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x4E2D;&#x58F0;&#x660E;&#xFF0C;&#x5728;&#x8FD9;&#x4E2A;&#x4F8B;&#x5B50;&#x4E2D;&#x4E3A;sayHello2&#xFF08;&#xFF09;&#x3002;&#x5728;JavaScript&#x4E2D;&#xFF0C;&#x5982;&#x679C;&#x5728;&#x53E6;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x4E2D;&#x4F7F;&#x7528;function&#x5173;&#x952E;&#x5B57;&#xFF0C;&#x5219;&#x8981;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;&#x95ED;&#x5305;&#x3002;</p>
    778. 

  778. <p>&#x5728;C&#x548C;&#x5927;&#x591A;&#x6570;&#x5176;&#x4ED6;&#x5E38;&#x7528;&#x8BED;&#x8A00;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x540E;&#xFF0C;&#x6240;&#x6709;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x4E0D;&#x518D;&#x53EF;&#x8BBF;&#x95EE;&#xFF0C;&#x56E0;&#x4E3A;&#x5806;&#x6808;&#x5E27;&#x88AB;&#x9500;&#x6BC1;&#x3002;</p>
    779. 

  779. <p>&#x5728;JavaScript&#x4E2D;&#xFF0C;&#x5982;&#x679C;&#x5728;&#x53E6;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x4E2D;&#x58F0;&#x660E;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#xFF0C;&#x90A3;&#x4E48;&#x5728;&#x4ECE;&#x8C03;&#x7528;&#x7684;&#x51FD;&#x6570;&#x8FD4;&#x56DE;&#x540E;&#xFF0C;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x4ECD;&#x7136;&#x53EF;&#x4EE5;&#x8BBF;&#x95EE;&#x3002;&#x8FD9;&#x662F;&#x4E0A;&#x9762;&#x6F14;&#x793A;&#x7684;&#xFF0C;&#x56E0;&#x4E3A;&#x6211;&#x4EEC;&#x8C03;&#x7528;&#x51FD;&#x6570;say2&#xFF08;&#xFF09;; &#x4E4B;&#x540E;&#x6211;&#x4EEC;&#x4ECE;sayHello2&#xFF08;&#xFF09;&#x8FD4;&#x56DE;&#x3002;&#x8BF7;&#x6CE8;&#x610F;&#xFF0C;&#x6211;&#x4EEC;&#x8C03;&#x7528;&#x7684;&#x4EE3;&#x7801;&#x5F15;&#x7528;&#x53D8;&#x91CF;text&#xFF0C;&#x5B83;&#x662F;&#x51FD;&#x6570;sayHello2&#xFF08;&#xFF09;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x3002;</p>
    780. 

  780. </blockquote>
    781. 

  781. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(text); } <span class="hljs-comment">// Output of say2.toString();</span>
    782. 

  782. </code></pre>
    783. 

  783. <blockquote>
    784. 

  784. <p>&#x770B;&#x770B;&#x8F93;&#x51FA;say2.toString()&#xFF0C;&#x6211;&#x4EEC;&#x53EF;&#x4EE5;&#x770B;&#x5230;&#x4EE3;&#x7801;&#x5F15;&#x7528;&#x7684;&#x53D8;&#x91CF;text&#x3002;&#x533F;&#x540D;&#x51FD;&#x6570;&#x53EF;&#x4EE5;&#x5F15;&#x7528;text&#x4FDD;&#x5B58;&#x503C;&#x7684;&#x503C;&apos;Hello Bob&apos;&#xFF0C;&#x56E0;&#x4E3A;&#x5C40;&#x90E8;&#x53D8;&#x91CF;sayHello2()&#x4FDD;&#x5B58;&#x5728;&#x95ED;&#x5305;&#x4E2D;&#x3002;</p>
    785. 

  785. <p>&#x795E;&#x5947;&#x7684;&#x662F;&#xFF0C;&#x5728;JavaScript&#x4E2D;&#xFF0C;&#x51FD;&#x6570;&#x5F15;&#x7528;&#x8FD8;&#x5177;&#x6709;&#x5BF9;&#x5176;&#x521B;&#x5EFA;&#x7684;&#x95ED;&#x5305;&#x7684;&#x79D8;&#x5BC6;&#x5F15;&#x7528; - &#x7C7B;&#x4F3C;&#x4E8E;&#x5982;&#x4F55;&#x59D4;&#x6258;&#x662F;&#x65B9;&#x6CD5;&#x6307;&#x9488;&#x52A0;&#x4E0A;&#x5BF9;&#x5BF9;&#x8C61;&#x7684;&#x79D8;&#x5BC6;&#x5F15;&#x7528;&#x3002;</p>
    786. 

  786. </blockquote>
    787. 

  787. <hr>
    788. 

  788. <h1 id="&#x66F4;&#x591A;&#x4F8B;&#x5B50;">&#x66F4;&#x591A;&#x4F8B;&#x5B50;</h1>
    789. 

  789. <p>&#x51FA;&#x4E8E;&#x67D0;&#x79CD;&#x539F;&#x56E0;&#xFF0C;&#x5F53;&#x4F60;&#x9605;&#x8BFB;&#x5173;&#x4E8E;&#x5B83;&#x4EEC;&#x7684;&#x95ED;&#x5305;&#x4F3C;&#x4E4E;&#x771F;&#x7684;&#x5F88;&#x96BE;&#x7406;&#x89E3;&#xFF0C;&#x4F46;&#x5F53;&#x4F60;&#x770B;&#x5230;&#x4E00;&#x4E9B;&#x4F8B;&#x5B50;&#xFF0C;&#x4F60;&#x53EF;&#x4EE5;&#x70B9;&#x51FB;&#x4ED6;&#x4EEC;&#x7684;&#x5DE5;&#x4F5C;&#xFF08;&#x5B83;&#x82B1;&#x4E86;&#x6211;&#x4E00;&#x6BB5;&#x65F6;&#x95F4;&#xFF09;&#x3002;&#x6211;&#x5EFA;&#x8BAE;&#x4ED4;&#x7EC6;&#x9605;&#x8BFB;&#x793A;&#x4F8B;&#xFF0C;&#x76F4;&#x5230;&#x4F60;&#x4E86;&#x89E3;&#x5B83;&#x4EEC;&#x5982;&#x4F55;&#x5DE5;&#x4F5C;&#x3002;&#x5982;&#x679C;&#x4F60;&#x5F00;&#x59CB;&#x4F7F;&#x7528;&#x95ED;&#x5305;&#x6CA1;&#x6709;&#x5B8C;&#x5168;&#x4E86;&#x89E3;&#x5B83;&#x4EEC;&#x5982;&#x4F55;&#x5DE5;&#x4F5C;&#xFF0C;&#x4F60;&#x5F88;&#x5FEB;&#x5C31;&#x4F1A;&#x521B;&#x5EFA;&#x4E00;&#x4E9B;&#x975E;&#x5E38;&#x53E4;&#x602A;&#x7684;&#x9519;&#x8BEF;&#xFF01;</p>
    790. 

  790. <h3 id="&#x4F8B;3">&#x4F8B;3</h3>
    791. 

  791. <blockquote>
    792. 

  792. <p>&#x6B64;&#x793A;&#x4F8B;&#x663E;&#x793A;&#x4E0D;&#x590D;&#x5236;&#x5C40;&#x90E8;&#x53D8;&#x91CF; - &#x5B83;&#x4EEC;&#x901A;&#x8FC7;&#x5F15;&#x7528;&#x4FDD;&#x7559;&#x3002;&#x5B83;&#x662F;&#x4E00;&#x79CD;&#x50CF;&#x5728;&#x5916;&#x90E8;&#x51FD;&#x6570;&#x9000;&#x51FA;&#x65F6;&#x5728;&#x5185;&#x5B58;&#x4E2D;&#x4FDD;&#x7559;&#x4E00;&#x4E2A;&#x5806;&#x6808;&#x6846;&#x67B6;&#xFF01;</p>
    793. 

  793. </blockquote>
    794. 

  794. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">say667</span>(<span class="hljs-params"></span>) </span>{
    795. 

  795.   <span class="hljs-comment">// Local variable that ends up within closure</span>
    796. 

  796.   <span class="hljs-keyword">var</span> num = <span class="hljs-number">42</span>;
    797. 

  797.   <span class="hljs-keyword">var</span> say = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(num); }
    798. 

  798.   num++;
    799. 

  799.   <span class="hljs-keyword">return</span> say;
    800. 

  800. }
    801. 

  801. <span class="hljs-keyword">var</span> sayNumber = say667();
    802. 

  802. sayNumber(); <span class="hljs-comment">// logs 43</span>
    803. 

  803. </code></pre>
    804. 

  804. <h3 id="&#x4F8B;4">&#x4F8B;4</h3>
    805. 

  805. <blockquote>
    806. 

  806. <p>&#x6240;&#x6709;&#x4E09;&#x4E2A;&#x5168;&#x5C40;&#x51FD;&#x6570;&#x5177;&#x6709;&#x5BF9;&#x540C;&#x4E00;&#x95ED;&#x5305;&#x7684;&#x516C;&#x5171;&#x5F15;&#x7528;&#xFF0C;&#x56E0;&#x4E3A;&#x5B83;&#x4EEC;&#x90FD;&#x5728;&#x5355;&#x4E2A;&#x8C03;&#x7528;&#x4E2D;&#x58F0;&#x660E;setupSomeGlobals()&#x3002;<br></p>
    807. 

  807. </blockquote>
    808. 

  808. <pre><code class="lang-js"><span class="hljs-keyword">var</span> gLogNumber, gIncreaseNumber, gSetNumber;
    809. 

  809. <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">setupSomeGlobals</span>(<span class="hljs-params"></span>) </span>{
    810. 

  810.   <span class="hljs-comment">// Local variable that ends up within closure</span>
    811. 

  811.   <span class="hljs-keyword">var</span> num = <span class="hljs-number">42</span>;
    812. 

  812.   <span class="hljs-comment">// Store some references to functions as global variables</span>
    813. 

  813.   gLogNumber = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(num); }
    814. 

  814.   gIncreaseNumber = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ num++; }
    815. 

  815.   gSetNumber = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">x</span>) </span>{ num = x; }
    816. 

  816. }
    817. 

  817. 

  818. setupSomeGlobals();
    819. 

  819. gIncreaseNumber();
    820. 

  820. gLogNumber(); <span class="hljs-comment">// 43</span>
    821. 

  821. gSetNumber(<span class="hljs-number">5</span>);
    822. 

  822. gLogNumber(); <span class="hljs-comment">// 5</span>
    823. 

  823. 

  824. <span class="hljs-keyword">var</span> oldLog = gLogNumber;
    825. 

  825. 

  826. setupSomeGlobals();
    827. 

  827. gLogNumber(); <span class="hljs-comment">// 42</span>
    828. 

  828. 

  829. oldLog() <span class="hljs-comment">// 5</span>
    830. 

  830. </code></pre>
    831. 

  831. <blockquote>
    832. 

  832. <p>&#x8FD9;&#x4E09;&#x4E2A;&#x51FD;&#x6570;&#x5177;&#x6709;&#x5BF9;&#x540C;&#x4E00;&#x95ED;&#x5305;&#x7684;&#x5171;&#x4EAB;&#x8BBF;&#x95EE; - setupSomeGlobals()&#x5F53;&#x5B9A;&#x4E49;&#x4E09;&#x4E2A;&#x51FD;&#x6570;&#x65F6;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x3002;<br>
    833. 

  833. &#x6CE8;&#x610F;&#xFF0C;&#x5728;&#x4E0A;&#x9762;&#x7684;&#x4F8B;&#x5B50;&#x4E2D;&#xFF0C;&#x5982;&#x679C;setupSomeGlobals()&#x518D;&#x6B21;&#x8C03;&#x7528;&#xFF0C;&#x5219;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;&#x65B0;&#x7684;&#x95ED;&#x5305;&#xFF08;stack-frame&#xFF01;&#xFF09;&#x3002;&#x8001;gLogNumber&#xFF0C;gIncreaseNumber&#xFF0C;gSetNumber&#x53D8;&#x91CF;&#x5C06;&#x8986;&#x76D6;&#x65B0;&#x7684;&#x5177;&#x6709;&#x65B0;&#x529F;&#x80FD;&#x5173;&#x95ED;&#x3002;&#xFF08;&#x5728;JavaScript&#x4E2D;&#xFF0C;&#x5F53;&#x4F60;&#x58F0;&#x660E;&#x53E6;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x5185;&#x7684;&#x51FD;&#x6570;&#xFF0C;&#x91CC;&#x9762;&#x7684;&#x529F;&#x80FD;&#xFF08;s&#xFF09;&#x662F;/&#x518D;&#x6B21;&#x91CD;&#x65B0;&#x521B;&#x5EFA;&#x6BCF;&#x4E2A;&#x5916;&#x90E8;&#x51FD;&#x6570;&#x88AB;&#x8C03;&#x7528;&#x65F6;&#xFF09;&#x3002;</p>
    834. 

  834. </blockquote>
    835. 

  835. <h3 id="&#x4F8B;5">&#x4F8B;5</h3>
    836. 

  836. <blockquote>
    837. 

  837. <p>&#x8FD9;&#x662F;&#x4E00;&#x4E2A;&#x771F;&#x6B63;&#x7684;&#x56F0;&#x6270;&#xFF0C;&#x8BB8;&#x591A;&#x4EBA;&#xFF0C;&#x6240;&#x4EE5;&#x4F60;&#x9700;&#x8981;&#x4E86;&#x89E3;&#x5B83;&#x3002;&#x8981;&#x975E;&#x5E38;&#x5C0F;&#x5FC3;&#xFF0C;&#x5982;&#x679C;&#x4F60;&#x5728;&#x4E00;&#x4E2A;&#x5FAA;&#x73AF;&#x4E2D;&#x5B9A;&#x4E49;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#xFF1A;&#x4ECE;&#x95ED;&#x5305;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x4E0D;&#x4F1A;&#x50CF;&#x4F60;&#x53EF;&#x80FD;&#x4F1A;&#x60F3;&#x7684;&#x90A3;&#x6837;&#x3002;</p>
    838. 

  838. </blockquote>
    839. 

  839. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">buildList</span>(<span class="hljs-params">list</span>) </span>{
    840. 

  840.     <span class="hljs-keyword">var</span> result = [];
    841. 

  841.     <span class="hljs-keyword">for</span> (<span class="hljs-keyword">var</span> i = <span class="hljs-number">0</span>; i &lt; list.length; i++) {
    842. 

  842.         <span class="hljs-keyword">var</span> item = <span class="hljs-string">&apos;item&apos;</span> + i;
    843. 

  843.         result.push( <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{<span class="hljs-built_in">console</span>.log(item + <span class="hljs-string">&apos; &apos;</span> + list[i])} );
    844. 

  844.     }
    845. 

  845.     <span class="hljs-keyword">return</span> result;
    846. 

  846. }
    847. 

  847. 

  848. <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">testList</span>(<span class="hljs-params"></span>) </span>{
    849. 

  849.     <span class="hljs-keyword">var</span> fnlist = buildList([<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>]);
    850. 

  850.     <span class="hljs-comment">// Using j only to help prevent confusion -- could use i.</span>
    851. 

  851.     <span class="hljs-keyword">for</span> (<span class="hljs-keyword">var</span> j = <span class="hljs-number">0</span>; j &lt; fnlist.length; j++) {
    852. 

  852.         fnlist[j]();
    853. 

  853.     }
    854. 

  854. }
    855. 

  855. 

  856.  testList() <span class="hljs-comment">//logs &quot;item2 undefined&quot; 3 times</span>
    857. 

  857. </code></pre>
    858. 

  858. <blockquote>
    859. 

  859. <p>line result.push&#xFF08;function&#xFF08;&#xFF09;{console.log&#xFF08;item +&apos;&apos;+ list [i]&#xFF09;}&#x5728;&#x7ED3;&#x679C;&#x6570;&#x7EC4;&#x4E2D;&#x6DFB;&#x52A0;&#x4E00;&#x4E2A;&#x5BF9;&#x533F;&#x540D;&#x51FD;&#x6570;&#x7684;&#x5F15;&#x7528;&#x4E09;&#x6B21;&#x3002;&#x5982;&#x679C;&#x4F60;&#x4E0D;&#x719F;&#x6089;&#x533F;&#x540D;&#x51FD;&#x6570;&#xFF0C; &#x5C31;&#x5982;&#xFF1A;</p>
    860. 

  860. </blockquote>
    861. 

  861. <pre><code class="lang-js">pointer = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{<span class="hljs-built_in">console</span>.log(item + <span class="hljs-string">&apos; &apos;</span> + list[i])};
    862. 

  862. result.push(pointer);
    863. 

  863. </code></pre>
    864. 

  864. <blockquote>
    865. 

  865. <p>&#x6CE8;&#x610F;&#xFF0C;&#x5F53;&#x8FD0;&#x884C;&#x793A;&#x4F8B;&#x65F6;&#xFF0C;&#x201C;item2 undefined&#x201D;&#x4F1A;&#x63D0;&#x9192;&#x4E09;&#x6B21;&#xFF01; &#x8FD9;&#x662F;&#x56E0;&#x4E3A;&#x5C31;&#x50CF;&#x524D;&#x9762;&#x7684;&#x4F8B;&#x5B50;&#x4E00;&#x6837;&#xFF0C;buildList&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x53EA;&#x6709;&#x4E00;&#x4E2A;&#x95ED;&#x5305;&#x3002; &#x5F53;&#x5728;fnlist [j]&#xFF08;&#xFF09;&#x4E0A;&#x8C03;&#x7528;&#x533F;&#x540D;&#x51FD;&#x6570;&#x65F6;; &#x5B83;&#x4EEC;&#x90FD;&#x4F7F;&#x7528;&#x76F8;&#x540C;&#x7684;&#x5355;&#x4E2A;&#x95ED;&#x5305;&#xFF0C;&#x5E76;&#x4E14;&#x5B83;&#x4EEC;&#x4F7F;&#x7528;&#x8BE5;&#x95ED;&#x5305;&#x5185;&#x7684;i&#x548C;&#x9879;&#x7684;&#x5F53;&#x524D;&#x503C;&#xFF08;&#x5176;&#x4E2D;i&#x5177;&#x6709;&#x503C;3&#xFF0C;&#x56E0;&#x4E3A;&#x5FAA;&#x73AF;&#x5DF2;&#x5B8C;&#x6210;&#xFF0C;&#x5E76;&#x4E14;&#x9879;&#x5177;&#x6709;&#x503C;&apos;item2&apos;&#xFF09;&#x3002; &#x6CE8;&#x610F;&#xFF0C;&#x6211;&#x4EEC;&#x4ECE;0&#x7D22;&#x5F15;&#xFF0C;&#x56E0;&#x6B64;&#x9879;&#x76EE;&#x7684;&#x503C;&#x4E3A;item2&#x3002; &#x5E76;&#x4E14;i ++&#x5C06;i&#x589E;&#x52A0;&#x5230;&#x503C;3&#x3002;</p>
    866. 

  866. </blockquote>
    867. 

  867. <h3 id="&#x4F8B;6">&#x4F8B;6</h3>
    868. 

  868. <blockquote>
    869. 

  869. <p>&#x6B64;&#x793A;&#x4F8B;&#x663E;&#x793A;&#xFF0C;&#x95ED;&#x5305;&#x5305;&#x542B;&#x5728;&#x9000;&#x51FA;&#x524D;&#x5728;&#x5916;&#x90E8;&#x51FD;&#x6570;&#x4E2D;&#x58F0;&#x660E;&#x7684;&#x4EFB;&#x4F55;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x3002; &#x6CE8;&#x610F;&#xFF0C;&#x53D8;&#x91CF;alice&#x5B9E;&#x9645;&#x4E0A;&#x662F;&#x5728;&#x533F;&#x540D;&#x51FD;&#x6570;&#x4E4B;&#x540E;&#x58F0;&#x660E;&#x7684;&#x3002; &#x533F;&#x540D;&#x51FD;&#x6570;&#x9996;&#x5148;&#x58F0;&#x660E;; &#x5E76;&#x4E14;&#x5F53;&#x8C03;&#x7528;&#x8BE5;&#x51FD;&#x6570;&#x65F6;&#xFF0C;&#x5B83;&#x53EF;&#x4EE5;&#x8BBF;&#x95EE;alice&#x53D8;&#x91CF;&#xFF0C;&#x56E0;&#x4E3A;alice&#x5728;&#x540C;&#x4E00;&#x8303;&#x56F4;&#x5185;&#xFF08;JavaScript&#x53D8;&#x91CF;&#x63D0;&#x5347;&#xFF09;&#x3002; &#x53E6;&#x5916;sayAlice&#xFF08;&#xFF09;&#xFF08;&#xFF09;&#x53EA;&#x662F;&#x76F4;&#x63A5;&#x8C03;&#x7528;&#x4ECE;sayAlice&#xFF08;&#xFF09;&#x8FD4;&#x56DE;&#x7684;&#x51FD;&#x6570;&#x5F15;&#x7528; - &#x5B83;&#x5B8C;&#x5168;&#x4E0E;&#x4EE5;&#x524D;&#x505A;&#x8FC7;&#x7684;&#x76F8;&#x540C;&#xFF0C;&#x4F46;&#x6CA1;&#x6709;&#x4E34;&#x65F6;&#x53D8;&#x91CF;&#x3002;</p>
    870. 

  870. </blockquote>
    871. 

  871. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">sayAlice</span>(<span class="hljs-params"></span>) </span>{
    872. 

  872.     <span class="hljs-keyword">var</span> say = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(alice); }
    873. 

  873.     <span class="hljs-comment">// Local variable that ends up within closure</span>
    874. 

  874.     <span class="hljs-keyword">var</span> alice = <span class="hljs-string">&apos;Hello Alice&apos;</span>;
    875. 

  875.     <span class="hljs-keyword">return</span> say;
    876. 

  876. }
    877. 

  877. sayAlice()();<span class="hljs-comment">// logs &quot;Hello Alice&quot;</span>
    878. 

  878. </code></pre>
    879. 

  879. <blockquote>
    880. 

  880. <p>Tricky&#xFF1A;&#x8FD8;&#x8981;&#x6CE8;&#x610F;&#xFF0C;say&#x53D8;&#x91CF;&#x4E5F;&#x5728;&#x95ED;&#x5305;&#x5185;&#xFF0C;&#x5E76;&#x4E14;&#x53EF;&#x4EE5;&#x88AB;&#x53EF;&#x80FD;&#x88AB;&#x58F0;&#x660E;&#x7684;&#x4EFB;&#x4F55;&#x5176;&#x4ED6;&#x51FD;&#x6570;&#x8BBF;&#x95EE;sayAlice()&#xFF0C;&#x6216;&#x8005;&#x5B83;&#x53EF;&#x4EE5;&#x5728;&#x5185;&#x90E8;&#x51FD;&#x6570;&#x5185;&#x88AB;&#x9012;&#x5F52;&#x5730;&#x8BBF;&#x95EE;&#x3002;</p>
    881. 

  881. </blockquote>
    882. 

  882. <h3 id="&#x4F8B;7">&#x4F8B;7</h3>
    883. 

  883. <blockquote>
    884. 

  884. <p>&#x6700;&#x540E;&#x4E00;&#x4E2A;&#x4F8B;&#x5B50;&#x663E;&#x793A;&#x6BCF;&#x4E2A;&#x8C03;&#x7528;&#x4E3A;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;&#x5355;&#x72EC;&#x7684;&#x95ED;&#x5305;&#x3002; &#x6BCF;&#x4E2A;&#x51FD;&#x6570;&#x58F0;&#x660E;&#x6CA1;&#x6709;&#x5355;&#x4E2A;&#x95ED;&#x5305;&#x3002; &#x6BCF;&#x4E2A;&#x51FD;&#x6570;&#x7684;&#x8C03;&#x7528;&#x90FD;&#x6709;&#x4E00;&#x4E2A;&#x95ED;&#x5305;&#x3002;</p>
    885. 

  885. </blockquote>
    886. 

  886. <pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">newClosure</span>(<span class="hljs-params">someNum, someRef</span>) </span>{
    887. 

  887.     <span class="hljs-comment">// Local variables that end up within closure</span>
    888. 

  888.     <span class="hljs-keyword">var</span> num = someNum;
    889. 

  889.     <span class="hljs-keyword">var</span> anArray = [<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>];
    890. 

  890.     <span class="hljs-keyword">var</span> ref = someRef;
    891. 

  891.     <span class="hljs-keyword">return</span> <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">x</span>) </span>{
    892. 

  892.         num += x;
    893. 

  893.         anArray.push(num);
    894. 

  894.         <span class="hljs-built_in">console</span>.log(<span class="hljs-string">&apos;num: &apos;</span> + num +
    895. 

  895.             <span class="hljs-string">&apos;; anArray: &apos;</span> + anArray.toString() +
    896. 

  896.             <span class="hljs-string">&apos;; ref.someVar: &apos;</span> + ref.someVar + <span class="hljs-string">&apos;;&apos;</span>);
    897. 

  897.       }
    898. 

  898. }
    899. 

  899. obj = {someVar: <span class="hljs-number">4</span>};
    900. 

  900. fn1 = newClosure(<span class="hljs-number">4</span>, obj);
    901. 

  901. fn2 = newClosure(<span class="hljs-number">5</span>, obj);
    902. 

  902. fn1(<span class="hljs-number">1</span>); <span class="hljs-comment">// num: 5; anArray: 1,2,3,5; ref.someVar: 4;</span>
    903. 

  903. fn2(<span class="hljs-number">1</span>); <span class="hljs-comment">// num: 6; anArray: 1,2,3,6; ref.someVar: 4;</span>
    904. 

  904. obj.someVar++;
    905. 

  905. fn1(<span class="hljs-number">2</span>); <span class="hljs-comment">// num: 7; anArray: 1,2,3,5,7; ref.someVar: 5;</span>
    906. 

  906. fn2(<span class="hljs-number">2</span>); <span class="hljs-comment">// num: 8; anArray: 1,2,3,6,8; ref.someVar: 5;</span>
    907. 

  907. </code></pre>
    908. 

  908. <hr>
    909. 

  909. <h2 id="&#x6982;&#x8981;">&#x6982;&#x8981;</h2>
    910. 

  910. <blockquote>
    911. 

  911. <p>&#x5982;&#x679C;&#x4E00;&#x5207;&#x4F3C;&#x4E4E;&#x5B8C;&#x5168;&#x4E0D;&#x6E05;&#x695A;&#xFF0C;&#x90A3;&#x4E48;&#x6700;&#x597D;&#x7684;&#x529E;&#x6CD5;&#x662F;&#x73A9;&#x7684;&#x4F8B;&#x5B50;&#x3002;&#x9605;&#x8BFB;&#x89E3;&#x91CA;&#x6BD4;&#x7406;&#x89E3;&#x793A;&#x4F8B;&#x56F0;&#x96BE;&#x5F97;&#x591A;&#x3002;&#x6211;&#x5BF9;&#x95ED;&#x5305;&#x548C;&#x5806;&#x6808;&#x6846;&#x67B6;&#x7B49;&#x7684;&#x89E3;&#x91CA;&#x5728;&#x6280;&#x672F;&#x4E0A;&#x662F;&#x4E0D;&#x6B63;&#x786E;&#x7684; - &#x5B83;&#x4EEC;&#x662F;&#x7528;&#x4E8E;&#x5E2E;&#x52A9;&#x7406;&#x89E3;&#x7684;&#x7C97;&#x7565;&#x7B80;&#x5316;&#x3002;&#x4E00;&#x65E6;&#x57FA;&#x672C;&#x7684;&#x60F3;&#x6CD5;&#x662F;grokked&#xFF0C;&#x4F60;&#x53EF;&#x4EE5;&#x63D0;&#x53D6;&#x7EC6;&#x8282;&#x540E;&#x3002;</p>
    912. 

  912. </blockquote>
    913. 

  913. <h2 id="&#x603B;&#x7ED3;">&#x603B;&#x7ED3;:</h2>
    914. 

  914. <blockquote>
    915. 

  915. <p>1.&#x5F53;&#x4F60;function&#x5728;&#x53E6;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x91CC;&#x9762;&#x4F7F;&#x7528;&#x65F6;&#xFF0C;&#x4F7F;&#x7528;&#x95ED;&#x5305;&#x3002;</p>
    916. 

  916. <p>2.&#x6BCF;&#x5F53;&#x5728;&#x51FD;&#x6570;&#x4E2D;&#x4F7F;&#x7528;eval&#xFF08;&#xFF09;&#x65F6;&#xFF0C;&#x90FD;&#x4F1A;&#x4F7F;&#x7528;&#x95ED;&#x5305;&#x3002; eval&#x7684;&#x6587;&#x672C;&#x53EF;&#x4EE5;&#x5F15;&#x7528;&#x51FD;&#x6570;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#xFF0C;&#x5728;eval&#x4E2D;&#x751A;&#x81F3;&#x53EF;&#x4EE5;&#x4F7F;&#x7528;eval&#xFF08;&apos;var foo = ...&apos;&#xFF09;&#x521B;&#x5EFA;&#x65B0;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;</p>
    917. 

  917. <p>3.&#x5F53;&#x5728;&#x51FD;&#x6570;&#x4E2D;&#x4F7F;&#x7528;&#x65B0;&#x7684;Function&#xFF08;...&#xFF09;&#xFF08;Function&#x6784;&#x9020;&#x51FD;&#x6570;&#xFF09;&#x65F6;&#xFF0C;&#x5B83;&#x4E0D;&#x4F1A;&#x521B;&#x5EFA;&#x95ED;&#x5305;&#x3002; &#xFF08;&#x65B0;&#x51FD;&#x6570;&#x4E0D;&#x80FD;&#x5F15;&#x7528;&#x5916;&#x5C42;&#x51FD;&#x6570;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x3002;&#xFF09;</p>
    918. 

  918. <p>4.JavaScript&#x4E2D;&#x7684;&#x95ED;&#x5305;&#x5C31;&#x50CF;&#x4FDD;&#x7559;&#x6240;&#x6709;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x7684;&#x526F;&#x672C;&#xFF0C;&#x5C31;&#x50CF;&#x51FD;&#x6570;&#x9000;&#x51FA;&#x65F6;&#x4E00;&#x6837;&#x3002;</p>
    919. 

  919. <p>5.&#x6700;&#x597D;&#x662F;&#x8BA4;&#x4E3A;&#x95ED;&#x5305;&#x59CB;&#x7EC8;&#x53EA;&#x521B;&#x5EFA;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x7684;&#x5165;&#x53E3;&#xFF0C;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#x5C06;&#x6DFB;&#x52A0;&#x5230;&#x95ED;&#x5305;&#x4E2D;&#x3002;</p>
    920. 

  920. <p>6.&#x6BCF;&#x6B21;&#x8C03;&#x7528;&#x5177;&#x6709;&#x95ED;&#x5305;&#x7684;&#x51FD;&#x6570;&#x65F6;&#xFF0C;&#x90FD;&#x4F1A;&#x4FDD;&#x5B58;&#x4E00;&#x7EC4;&#x65B0;&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#xFF08;&#x5047;&#x5B9A;&#x51FD;&#x6570;&#x5728;&#x5176;&#x4E2D;&#x5305;&#x542B;&#x51FD;&#x6570;&#x58F0;&#x660E;&#xFF0C;&#x5E76;&#x4E14;&#x5BF9;&#x8BE5;&#x51FD;&#x6570;&#x7684;&#x5F15;&#x7528;&#x8981;&#x4E48;&#x8FD4;&#x56DE;&#xFF0C;&#x8981;&#x4E48;&#x4EE5;&#x67D0;&#x79CD;&#x65B9;&#x5F0F;&#x4FDD;&#x7559;&#x5916;&#x90E8;&#x5F15;&#x7528; &#xFF09;&#x3002;</p>
    921. 

  921. <p>7.&#x4E24;&#x4E2A;&#x51FD;&#x6570;&#x53EF;&#x80FD;&#x770B;&#x8D77;&#x6765;&#x50CF;&#x5B83;&#x4EEC;&#x5177;&#x6709;&#x76F8;&#x540C;&#x7684;&#x6E90;&#x6587;&#x672C;&#xFF0C;&#x4F46;&#x662F;&#x5177;&#x6709;&#x5B8C;&#x5168;&#x4E0D;&#x540C;&#x7684;&#x884C;&#x4E3A;&#xFF0C;&#x56E0;&#x4E3A;&#x5B83;&#x4EEC;&#x7684;&#x201C;&#x9690;&#x85CF;&#x201D;&#x95ED;&#x5305;&#x3002; &#x6211;&#x4E0D;&#x8BA4;&#x4E3A;JavaScript&#x4EE3;&#x7801;&#x5B9E;&#x9645;&#x4E0A;&#x53EF;&#x4EE5;&#x627E;&#x51FA;&#x4E00;&#x4E2A;&#x51FD;&#x6570;&#x5F15;&#x7528;&#x662F;&#x5426;&#x6709;&#x95ED;&#x5305;&#x3002;</p>
    922. 

  922. <p>8.&#x5982;&#x679C;&#x4F60;&#x8BD5;&#x56FE;&#x505A;&#x4EFB;&#x4F55;&#x52A8;&#x6001;&#x6E90;&#x4EE3;&#x7801;&#x4FEE;&#x6539;&#xFF08;&#x4F8B;&#x5982;&#xFF1A;myFunction = Function&#xFF08;myFunction.toString&#xFF08;&#xFF09;&#x3002;replace&#xFF08;/ Hello /&#xFF0C;&apos;Hola&apos;&#xFF09;&#xFF09;;&#xFF09;&#xFF0C;&#x5982;&#x679C;myFunction&#x662F;&#x4E00;&#x4E2A;&#x95ED;&#x5305; &#x5F53;&#x7136;&#xFF0C;&#x4F60;&#x6C38;&#x8FDC;&#x4E0D;&#x4F1A;&#x60F3;&#x5230;&#x5728;&#x8FD0;&#x884C;&#x65F6;&#x505A;&#x6E90;&#x4EE3;&#x7801;&#x5B57;&#x7B26;&#x4E32;&#x66FF;&#x6362;&#xFF0C;&#x4F46;...&#xFF09;&#x3002;</p>
    923. 

  923. <p>9.&#x53EF;&#x4EE5;&#x5728;&#x51FD;&#x6570;&#x5185;&#x7684;&#x51FD;&#x6570;&#x58F0;&#x660E;&#x4E2D;&#x83B7;&#x5F97;&#x51FD;&#x6570;&#x58F0;&#x660E; - &#x4F60;&#x53EF;&#x4EE5;&#x5728;&#x591A;&#x4E2A;&#x7EA7;&#x522B;&#x83B7;&#x5F97;&#x95ED;&#x5305;&#x3002;</p>
    924. 

  924. <p>10.&#x6211;&#x8BA4;&#x4E3A;&#x901A;&#x5E38;&#x95ED;&#x5305;&#x662F;&#x51FD;&#x6570;&#x548C;&#x6355;&#x83B7;&#x7684;&#x53D8;&#x91CF;&#x7684;&#x672F;&#x8BED;&#x3002; &#x6CE8;&#x610F;&#xFF0C;&#x6211;&#x5728;&#x672C;&#x6587;&#x4E2D;&#x4E0D;&#x4F7F;&#x7528;&#x8FD9;&#x4E2A;&#x5B9A;&#x4E49;&#xFF01;</p>
    925. 

  925. <p>11.&#x6211;&#x6000;&#x7591;JavaScript&#x4E2D;&#x7684;&#x95ED;&#x5305;&#x4E0D;&#x540C;&#x4E8E;&#x901A;&#x5E38;&#x5728;&#x51FD;&#x6570;&#x5F0F;&#x8BED;&#x8A00;&#x4E2D;&#x53D1;&#x73B0;&#x7684;&#x95ED;&#x5305;&#x3002;</p>
    926. 

  926. </blockquote>
    927. 

  927. <h2 id="&#x94FE;&#x63A5;">&#x94FE;&#x63A5;:</h2>
    928. 

  928. <blockquote>
    929. 

  929. <p>1.Douglas Crockford&#x7684;&#x6A21;&#x62DF;<a href="http://www.crockford.com/javascript/private.html" target="_blank">&#x79C1;&#x6709;&#x5C5E;&#x6027;&#x548C;&#x4E00;&#x4E2A;&#x5BF9;&#x8C61;&#x7684;&#x79C1;&#x6709;&#x65B9;&#x6CD5;</a>&#xFF0C;&#x4F7F;&#x7528;&#x95ED;&#x5305;&#x3002;</p>
    930. 

  930. <p>2.&#x4E00;&#x4E2A;&#x4F1F;&#x5927;&#x7684;&#x89E3;&#x91CA;&#x5982;&#x4F55;&#x95ED;&#x5305;&#x53EF;&#x4EE5;&#x5BFC;&#x81F4;<a href="https://www.codeproject.com/Articles/12231/Memory-Leakage-in-Internet-Explorer-revisited" target="_blank">&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x5728;IE</a>&#x5982;&#x679C;&#x4F60;&#x4E0D;&#x5C0F;&#x5FC3;&#x3002;</p>
    931. 

  931. </blockquote>
    932. 

  932. <h2 id="&#x611F;&#x8C22;">&#x611F;&#x8C22;</h2>
    933. 

  933. <blockquote>
    934. 

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    935. 

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