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</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><p>就可以通过如下方式来调用：</p> <h4 id="使用场景"><a href="#使用场景" class="header-anchor">#</a> 使用场景</h4> <p>参数明确使用<code>call</code>,参数不明确使用<code>apply</code>;</p> <div class="language-js line-numbers-mode"><pre class="language-js"><code><span class="token function">func</span><span class="token punctuation">.</span><span class="token function">call</span><span class="token punctuation">(</span><span class="token keyword">this</span><span class="token punctuation">,</span> arg1<span class="token punctuation">,</span> arg2<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token function">func</span><span class="token punctuation">.</span><span class="token function">apply</span><span class="token punctuation">(</span><span class="token keyword">this</span><span class="token punctuation">,</span> <span class="token punctuation">[</span>arg1<span class="token punctuation">,</span> arg2<span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div><h2 id="bind"><a href="#bind" class="header-anchor">#</a> bind</h2> <p><code>MDN</code>的解释是：<code>bind()</code>方法会创建一个新函数，称为绑定函数，当调用这个绑定函数时，绑定函数会以创建它时传入 bind()方法的第一个参数作为 <code>this</code>，传入 <code>bind()</code> 方法的第二个以及以后的参数加上绑定函数运行时本身的参数按照顺序作为原函数的参数来调用原函数。</p> <h2 id="总结"><a href="#总结" class="header-anchor">#</a> 总结</h2> <ul><li><code>apply</code>、<code>call</code> 、<code>bind</code>三者都是用来改变函数的<code>this</code>对象的指向的;</li> <li><code>apply</code>、<code>call</code> 、<code>bind</code>三者第一个参数都是 this 要指向的对象，也就是想指定的上下文;</li> <li><code>apply</code>、<code>call</code> 、<code>bind</code>三者都可以利用后续参数传参;</li> <li><code>bind</code>是返回对应函数,便于稍后调用;<code>apply</code>、<code>call</code>则是立即调用.</li></ul> <h4 id="学习资料"><a href="#学习资料" class="header-anchor">#</a> 学习资料</h4> <ul><li><a href="https://www.cnblogs.com/coco1s/p/4833199.html" target="_blank" rel="noopener noreferrer">【优雅代码】深入浅出 妙用 Javascript 中 apply、call、bind<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a></li> <li><a href="https://juejin.im/post/59bfe84351882531b730bac2" target="_blank" rel="noopener noreferrer">this、apply、call、bind<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a></li> <li><a href="https://juejin.im/post/5a9640335188257a7924d5ef" target="_blank" rel="noopener noreferrer">让你弄懂 call、apply、bind 的应用和区别<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a></li></ul></div> <footer class="page-edit"><!----> <div class="last-updated"><span class="prefix">Last Updated:</span> <span class="time">7/16/2019, 10:09:07 PM</span></div></footer> <!----> </main></div><div class="global-ui"></div></div>
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