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JavaScript-object.html
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<h1>JavaScript 数据类型之(对象)</h1>
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<a>2020年11月18日</a>
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<a class=" -link" href="/categories/JavaScript/">JavaScript</a>
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<ol class="toc"><li class="toc-item toc-level-1"><a class="toc-link" href="#JavaScript%E4%B9%9F%E6%98%AF%E4%B8%80%E7%A7%8D%E9%9D%A2%E5%90%91%E5%AF%B9%E8%B1%A1%E7%9A%84%E8%AF%AD%E8%A8%80-%E6%89%80%E6%9C%89%E7%9A%84%E9%94%AE%E9%83%BD%E6%98%AF%E5%AD%97%E7%AC%A6%E4%B8%B2-%E5%80%BC%E5%8F%AF%E4%BB%A5%E6%98%AF%E4%BB%BB%E6%84%8F%E5%AF%B9%E8%B1%A1"><span class="toc-text">JavaScript也是一种面向对象的语言 所有的键都是字符串 值可以是任意对象</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E5%AF%B9%E8%B1%A1%E8%B5%8B%E5%80%BC"><span class="toc-text">对象赋值</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#undefined-%E4%BD%BF%E7%94%A8%E4%B8%8D%E5%AD%98%E5%9C%A8%E5%AF%B9%E8%B1%A1-%E4%B8%8D%E4%BC%9A%E6%8A%A5%E9%94%99"><span class="toc-text">undefined 使用不存在对象, 不会报错</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#delete-%E5%8A%A8%E6%80%81%E7%9A%84%E5%88%A0%E5%87%8F%E5%B1%9E%E6%80%A7"><span class="toc-text">delete 动态的删减属性</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E5%8A%A8%E6%80%81%E7%9A%84%E6%B7%BB%E5%8A%A0%E7%BB%99%E6%96%B0%E7%9A%84%E5%B1%9E%E6%80%A7%E6%B7%BB%E5%8A%A0%E5%80%BC"><span class="toc-text">动态的添加给新的属性添加值</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E5%88%A4%E6%96%AD%E5%B1%9E%E6%80%A7%E5%80%BC%E6%98%AF%E5%90%A6%E5%9C%A8%E8%BF%99%E4%B8%AA%E5%AF%B9%E8%B1%A1-%E5%B1%9E%E6%80%A7%E5%80%BC%E6%98%AF%E5%90%A6%E5%9C%A8%E8%BF%99%E4%B8%AA%E5%AF%B9%E8%B1%A1"><span class="toc-text">判断属性值是否在这个对象 属性值是否在这个对象</span></a></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E5%88%A4%E6%96%AD%E5%B1%9E%E6%80%A7%E6%98%AF%E5%90%A6%E6%98%AF%E8%BF%99%E4%B8%AA%E5%AF%B9%E8%B1%A1%E8%87%AA%E8%BA%AB%E6%8B%A5%E6%9C%89%E7%9A%84-hasOwnProperty"><span class="toc-text">判断属性是否是这个对象自身拥有的 hasOwnProperty()</span></a></li></ol>
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<p><strong>JavaScript个人整理</strong></p>
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<h1 id="JavaScript也是一种面向对象的语言-所有的键都是字符串-值可以是任意对象"><a href="#JavaScript也是一种面向对象的语言-所有的键都是字符串-值可以是任意对象" class="headerlink" title="JavaScript也是一种面向对象的语言 所有的键都是字符串 值可以是任意对象"></a>JavaScript也是一种面向对象的语言 所有的键都是字符串 值可以是任意对象</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript"><span class="hljs-keyword">var</span> 对象名 = { <br> 属性名: 属性值<br> 属性名: 属性值<br> 属性名: 属性值<br>} <br><br><span class="hljs-comment">/*通过下标取值和赋值*/</span><br><span class="hljs-keyword">var</span> person = {<br> <span class="hljs-attr">name</span>: <span class="hljs-string">"sdq"</span>,<br> <span class="hljs-attr">age</span>: <span class="hljs-number">3</span>,<br> <span class="hljs-attr">email</span>: <span class="hljs-string">"???????@???"</span><br> <span class="hljs-attr">score</span>: <span class="hljs-number">0</span><br>}<br></code></pre></td></tr></table></figure>
<p><strong>若干个键值对 js中对象, {…..}表示一个对象, 键值对描述属性xxxx: xxxx, 多个属性之间使用逗号隔开, 最后一个属性不加逗号</strong></p>
<h1 id="对象赋值"><a href="#对象赋值" class="headerlink" title="对象赋值"></a>对象赋值</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript">person.<span class="hljs-property">name</span> = <span class="hljs-string">"sdq"</span> <span class="hljs-comment">/*这里赋值sdq*/</span><br>person.<span class="hljs-property">name</span> <span class="hljs-comment">/*这里输出sdq*/</span><br></code></pre></td></tr></table></figure>
<h1 id="undefined-使用不存在对象-不会报错"><a href="#undefined-使用不存在对象-不会报错" class="headerlink" title="undefined 使用不存在对象, 不会报错"></a>undefined 使用不存在对象, 不会报错</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript">person.<span class="hljs-property">sdz</span><br><span class="hljs-literal">undefined</span><br></code></pre></td></tr></table></figure>
<h1 id="delete-动态的删减属性"><a href="#delete-动态的删减属性" class="headerlink" title="delete 动态的删减属性"></a>delete 动态的删减属性</h1><p><strong>例子</strong></p>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript"><span class="hljs-keyword">delete</span> person.<span class="hljs-property">name</span><br><span class="hljs-literal">true</span><br>person<br></code></pre></td></tr></table></figure>
<h1 id="动态的添加给新的属性添加值"><a href="#动态的添加给新的属性添加值" class="headerlink" title="动态的添加给新的属性添加值"></a>动态的添加给新的属性添加值</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript">person.<span class="hljs-property">sdq</span> = <span class="hljs-string">"sdz"</span> <span class="hljs-comment">/*这里赋值sdz*/</span><br>person <br></code></pre></td></tr></table></figure>
<h1 id="判断属性值是否在这个对象-属性值是否在这个对象"><a href="#判断属性值是否在这个对象-属性值是否在这个对象" class="headerlink" title="判断属性值是否在这个对象 属性值是否在这个对象"></a>判断属性值是否在这个对象 属性值是否在这个对象</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript"><span class="hljs-string">"sdq"</span> <span class="hljs-keyword">in</span> person <br><span class="hljs-literal">true</span> <br><span class="hljs-string">"sdqz"</span> <span class="hljs-keyword">in</span> person <br><span class="hljs-literal">false</span><br></code></pre></td></tr></table></figure>
<h1 id="判断属性是否是这个对象自身拥有的-hasOwnProperty"><a href="#判断属性是否是这个对象自身拥有的-hasOwnProperty" class="headerlink" title="判断属性是否是这个对象自身拥有的 hasOwnProperty()"></a>判断属性是否是这个对象自身拥有的 hasOwnProperty()</h1><figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><code class="hljs JavaScript">person.<span class="hljs-title function_">hasOwnProperty</span>(<span class="hljs-string">"toString"</span>)<br><span class="hljs-literal">false</span> <br>person.<span class="hljs-title function_">hasOwnProperty</span>(<span class="hljs-string">"sdq"</span>)<br><span class="hljs-literal">true</span><br></code></pre></td></tr></table></figure>
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<strong>本文作者：</strong>
史迪奇<br>
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