js for in 循环注意事项

<p>最近在使用for...in遍历数组，结果把原型链中的信息也改遍历出来了&nbsp;<br/></p><p><img src="http://img.80zx.com/ueditor/image/202009/1600913502b43136.jpg" title="for-in2" alt="for-in2"/></p><pre style="background-color:#262e37;color:#ffffff;font-family:&#39;Consolas&#39;;font-size:11.3pt;"><span style="color:#660e7a;font-weight:bold;font-style:italic;">$</span>.<span style="color:#4ac60a;">ajax</span>({<br/> <span style="color:#660e7a;font-weight:bold;">type</span><span style="color:#f92672;">: </span><span style="color:#e6db74;">&quot;get&quot;</span>,<br/> <span style="color:#660e7a;font-weight:bold;">url</span><span style="color:#f92672;">: </span><span style="color:#660e7a;font-weight:bold;font-style:italic;">domain </span><span style="color:#f92672;">+ </span><span style="color:#e6db74;">&quot;/Search/GetEK&quot;</span>,<br/> <span style="color:#660e7a;font-weight:bold;">async</span><span style="color:#f92672;">: true</span>,<br/> <span style="color:#660e7a;font-weight:bold;">data</span><span style="color:#f92672;">: </span>{<br/> <span style="color:#e6db74;">&quot;keyword&quot;</span><span style="color:#f92672;">: </span><span style="color:#64a2a2;">a<br/></span><span style="color:#64a2a2;"> &nbsp; &nbsp;</span>},<br/> <span style="color:#4ac60a;">success</span><span style="color:#f92672;">: function</span>(<span style="color:#fd971f;font-style:italic;">c</span>) {<br/> <span style="color:#f92672;">var </span><span style="color:#64a2a2;">d </span><span style="color:#f92672;">= </span><span style="color:#660e7a;font-weight:bold;font-style:italic;">JSON</span>.<span style="color:#4ac60a;">parse</span>(<span style="color:#fd971f;font-style:italic;">c</span>);<br/> <span style="color:#f92672;">var </span><span style="color:#64a2a2;">f </span><span style="color:#f92672;">= </span><span style="color:#64a2a2;">d</span>.<span style="color:#660e7a;font-weight:bold;">data</span>;<br/> <span style="color:#f92672;">var </span><span style="color:#64a2a2;">g </span><span style="color:#f92672;">= </span><span style="color:#e6db74;">&quot;&quot;</span>;<br/> <span style="color:#f92672;">for </span>(<span style="color:#f92672;">var </span><span style="color:#64a2a2;">e </span><span style="color:#f92672;">in </span><span style="color:#64a2a2;">f</span>) {<br/> <span style="color:#f92672;">if</span>(<span style="color:#f92672;">!</span><span style="color:#660e7a;font-weight:bold;font-style:italic;">Object</span>.<span style="color:#660e7a;font-weight:bold;">prototype</span>.<span style="color:#4ac60a;">hasOwnProperty</span>.<span style="color:#4ac60a;">call</span>(<span style="color:#64a2a2;">f</span>,<span style="color:#64a2a2;">e</span>)) <span style="color:#f92672;">continue</span>; <span style="color:#5b7773;background-color:#191f26;">//</span><span style="color:#5b7773;background-color:#191f26;font-family:&#39;宋体&#39;;">添加此判断代码跳过</span><span style="color:#5b7773;font-family:&#39;宋体&#39;;"><br/></span><span style="color:#5b7773;font-family:&#39;宋体&#39;;"> &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</span><span style="color:#64a2a2;">g </span><span style="color:#f92672;">+= </span><span style="color:#e6db74;">&#39;&lt;a href=&quot;/prosearch.html?text=&#39; </span><span style="color:#f92672;">+ </span><span style="color:#64a2a2;">f</span>[<span style="color:#64a2a2;">e</span>] <span style="color:#f92672;">+ </span><span style="color:#e6db74;">&#39;&quot;&gt;&#39; </span><span style="color:#f92672;">+ </span><span style="color:#64a2a2;">f</span>[<span style="color:#64a2a2;">e</span>] <span style="color:#f92672;">+ </span><span style="color:#e6db74;">&quot;&lt;/a&gt;&quot;<br/></span><span style="color:#e6db74;"> &nbsp; &nbsp; &nbsp; &nbsp;</span>}<br/> <span style="font-style:italic;">$</span>(<span style="color:#e6db74;">&quot;#tipCons&quot;</span>).<span style="color:#4ac60a;">html</span>(<span style="color:#64a2a2;">g</span>)<br/> }<br/>})</pre><p>参考：https://www.jianshu.com/p/b56a8c68a847</p>