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Introduction
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<span><b>1.</b> 面向对象</span>
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构造函数
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<b>1.4.</b>
面向对象的三大特性
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<span><b>1.5.</b> 原型</span>
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传统构造函数存在的问题
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使用原型解决构造函数问题
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<b>1.5.4.</b>
原型的使用
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<b>1.5.5.</b>
\_\_proto\_\_
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继承的实现方式
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<b>1.7.</b>
原型三角绘制
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属性搜索原则
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<b>1.9.1.</b>
原型链结构
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<b>1.9.2.</b>
原型式继承
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<span><b>1.10.</b> 对象相关的其他知识</span>
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<b>1.10.1.</b>
Object.prototype成员介绍
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Function
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Function的使用
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参数代码太长的问题
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静态成员和实例成员
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<b>1.10.4.</b>
arguments对象
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<h2 id="arguments对象">arguments对象</h2>
<p>在每一个函数调用的过程中, 函数代码体内有一个默认的对象<code>arguments</code>, 它存储着实际传入的所有参数。</p>
<p><code>arguments</code>是一个伪数组对象. 它表示在函数调用的过程中传入的所有参数的集合。在函数调用过程中不规定参数的个数与类型, 可以使得函数调用变得非常灵活性。</p>
<p>JavaScript中的函数并没有规定必须如何传参：</p>
<ol>
<li>定义函数的时候不写参数, 一样可以调用时传递参数</li>
<li>定义的时候写了参数, 调用的时候可以不传参</li>
<li>定义的时候写了一个参数, 调用的时候可以随意的传递多个而参数</li>
</ol>
<p>在代码设计中, 如果需要函数带有任意个参数的时候, 一般就不带任何参数, 所有的参数利用<code>arguments</code>对象来获取. 一般的函数定义语法, 可以写成:</p>
<pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">foo</span> (<span class="hljs-params"> <span class="hljs-comment">/* ... */</span> </span>) </span>{
}
</code></pre>
<h3 id="练习">练习:</h3>
<blockquote>
<p>利用 Function 创建一个函数, 要求允许函数调用时传入任意个数参数, 并且函数返回这些数字中最大的数字.</p>
</blockquote>
<pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">foo</span> (<span class="hljs-params"> </span>) </span>{
<span class="hljs-comment">// 所有的参数都在 arguments 中. 将其当做数组使用</span>
<span class="hljs-comment">// 问题已转换成在有一个数组中求最大值</span>
<span class="hljs-keyword">var</span> args = <span class="hljs-built_in">arguments</span>;
<span class="hljs-keyword">var</span> max = args[ <span class="hljs-number">0</span> ];
<span class="hljs-keyword">for</span> ( <span class="hljs-keyword">var</span> i = <span class="hljs-number">1</span>; i < args.length; i++ ) {
<span class="hljs-keyword">if</span> ( max < args[ i ] ) {
max = args[ i ];
}
}
<span class="hljs-keyword">return</span> max;
}
</code></pre>
<h3 id="练习">练习:</h3>
<blockquote>
<p>利用 Function 写一个函数, 要求传入任意个数字 求和</p>
</blockquote>
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