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this page</button></div><div class="theme-doc-markdown markdown"><h1>常见框架的 Diff 算法</h1><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="相关问题">相关问题<a class="hash-link" href="#相关问题" title="Direct link to heading"></a></h2><ul><li>虚拟 DOM 是什么</li><li>虚拟 DOM 的作用</li><li>讲一下 Vue 的 Diff 算法</li></ul><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="回答关键点">回答关键点<a class="hash-link" href="#回答关键点" title="Direct link to heading"></a></h2><p><code>虚拟 DOM</code> <code>时间复杂度O(n)</code></p><p>现代网站大多具有复杂布局,大量的节点和交互操作等特征,直接操作 DOM 方法不当带来的性能问题不可忽视。虚拟 DOM 的本质是 JavaScript 对象,它可以代表 DOM 的一部分特征,是 DOM 的抽象简化版本。通过预先操作虚拟 DOM,在某个时机找出和真实 DOM 之间的差异部分并重新渲染,来提升操作真实 DOM 的性能和效率。</p><p>为达到这个目的,还需要关注两个问题:什么时候重新渲染,怎么高效选择重新渲染的范围。找出需要重新渲染的范围,就是 Diff 的过程。React 和 Vue 的 Diff 算法思路基本一致,只对同层节点进行比较,利用唯一标识符对节点进行区分。</p><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="知识点深入">知识点深入<a class="hash-link" href="#知识点深入" title="Direct link to heading"></a></h2><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="1-diff-算法">1. Diff 算法<a class="hash-link" href="#1-diff-算法" title="Direct link to heading"></a></h3><p>两棵树的比对和更新,涉及到树编辑距离(Tree Editing Distance)算法:将一棵树转化为另一棵树的最小操作成本。操作类型包括:删除、插入、修改。时间复杂度为 O(n^3)。</p><p>为了降低时间复杂度,React 和 Vue 的思路是基于以下两个假设条件,缩减递归迭代规模,将 Diff 算法的时间复杂度降低为 O(n):</p><ol><li>相同类型的组件产生相同的 DOM 结构,反之亦然。所以不同类型组件的结构不需要进一步递归 Diff。</li><li>同一层级的一组节点,可以通过唯一标识符进行区分。</li></ol><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="2-react-reconciliation">2. React Reconciliation<a class="hash-link" href="#2-react-reconciliation" title="Direct link to heading"></a></h3><p>在 React 中,将虚拟 DOM 和真实 DOM 进行比对然后同步的过程被称为 Reconciliation(调和),Fiber 是 React 16 中新的调和引擎。它的主要目标是实现虚拟 DOM 的增量渲染。</p><p>Diff 的大致过程是,当对比两棵虚拟 DOM 树时,React 先对比根元素。依据根元素的类型不同,会有不同的操作:</p><ol><li><p><strong>不同类型的元素</strong></p><p>如果元素的类型不同,React 会抛弃旧树并建立新树。如以下情况,会导致完全重建:</p><div class="codeBlockContainer_I0IT language-html theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-html codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic"><!-- old --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">button</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">class</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">bg-blue-100</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">button</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- new --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">div</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">class</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">bg-blue-100</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">div</span><span class="token tag punctuation" style="color:#393A34">></span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></li><li><p><strong>相同类型的元素</strong></p><p>如果元素是两个相同类型的 React DOM 元素时,React 会查看两者的属性,保留 DOM 节点,只更新改变的属性。如以下情况,React 只更新颜色样式。</p><div class="codeBlockContainer_I0IT language-html theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-html codeBlock_jd64 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class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">button</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- new --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">button</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">class</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">bg-red-100 text-center</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">button</span><span class="token tag punctuation" style="color:#393A34">></span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></li></ol><p>在元素类型相同的情况下,比对完元素后,会递归元素的子元素。默认情况下,React 会同时迭代新老两个子元素列表。对于列表的更新,React 建议在列表项中标识 key 属性。避免以下低效场景:</p><div class="codeBlockContainer_I0IT language-html theme-code-block"><div class="codeBlockContent_wNvx" style="color:#393A34;background-color:#f6f8fa"><pre tabindex="0" class="prism-code language-html codeBlock_jd64 thin-scrollbar"><code class="codeBlockLines_mRuA"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic"><!-- bad --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- React 不会意识到可以保留<li>HZFE</li>和<li>Front-End</li>子树的完整,而是重写每个元素 --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- old --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Front-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- new --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Back-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Front-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- good --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- 子列表项有稳定且在兄弟节点中唯一的 key 属性, --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- React 使用 key 从新老树中匹配对应节点比较,提高 Diff 效率。 --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- old --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">key</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">2016</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">key</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">2017</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Front-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic"><!-- new --></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">key</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">2015</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Back-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">key</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">2016</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">HZFE</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token tag punctuation" style="color:#393A34"><</span><span class="token tag" style="color:#00009f">li</span><span class="token tag" style="color:#00009f"> </span><span class="token tag attr-name" style="color:#00a4db">key</span><span class="token tag attr-value punctuation attr-equals" style="color:#393A34">=</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag attr-value" style="color:#e3116c">2017</span><span class="token tag attr-value punctuation" style="color:#393A34">"</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain">Front-End</span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">li</span><span class="token tag punctuation" style="color:#393A34">></span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token tag punctuation" style="color:#393A34"></</span><span class="token tag" style="color:#00009f">ul</span><span class="token tag punctuation" style="color:#393A34">></span><br></span></code></pre><button type="button" aria-label="Copy code to clipboard" title="Copy" class="copyButton_eDfN clean-btn"><span class="copyButtonIcons_W9eQ" aria-hidden="true"><svg class="copyButtonIcon_XEyF" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_i9w9" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div><h3 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="2-vue2x-diff">2. Vue2.x Diff<a class="hash-link" href="#2-vue2x-diff" title="Direct link to heading"></a></h3><p>Vue 的 Diff 算法和 React 的类似,只在同一层次进行比较,不进行跨层比较。如果两个元素被判定为不相同,则不继续递归比较。在 Diff 子元素的过程中,采用双端比较的方法,设立 4 个指针:</p><ul><li>oldStartIdx 指向旧子元素列表中,从左边开始 Diff 的元素索引。初始值:第一个元素的索引。</li><li>newStartIdx 指向新子元素列表中,从左边开始 Diff 的元素索引。初始值:第一个元素的索引。</li><li>oldEndIdx 指向旧子元素列表中,从右边开始 Diff 的元素索引。初始值:最后一个元素的索引。</li><li>newEndIdx 指向新子元素列表中,从右边开始 Diff 的元素索引。初始值:最后一个元素的索引。</li></ul><p><img loading="lazy" src="https://user-images.githubusercontent.com/17002181/130326547-7cdcbc06-b400-43d3-89ce-e73934e38bdf.png" alt="image" class="img_E7b_"></p><p>Vue 同时遍历新老子元素虚拟 DOM 列表,并采用头尾比较。一般有 4 种情况:</p><ol><li><p><strong>当新老 start 指针指向的是相同节点</strong></p><p>复用节点并按需更新。</p><p>新老 start 指针向右移动一位。</p></li><li><p><strong>当新老 end 指针指向的是相同节点</strong></p><p>复用节点并按需更新。</p><p>新老 end 指针向左移动一位。</p></li><li><p><strong>当老 start 指针和新 end 指针指向的是相同节点</strong></p><p>复用节点并按需更新,将节点对应的真实 DOM 移动到子元素列表队尾。</p><p>老 start 指针向右移动一位。</p><p>新 end 指针向左移动一位。</p></li><li><p><strong>当老 end 指针和新 start 指针指向的是相同节点</strong></p><p>复用节点并按需更新,将节点对应的真实 DOM 移动到子元素列表队头。</p><p>老 end 指针向左移动一位。</p><p>新 start 指针向右移动一位。</p></li></ol><p>在不满足以上情况的前提下,会尝试检查新 start 指针指向的节点是否有唯一标识符 key,如果有且能在旧列表中找到拥有相同 key 的相同类型节点,则可复用并按需更新,且移动节点到新的位置。新 start 指针向右移动一位。如果依旧不满足条件,则新增相关节点。</p><p>当新老列表的中任意一个列表的头指针索引大于尾指针索引时,循环遍历结束,按需删除或新增相关节点即可。</p><h2 class="anchor anchorWithHideOnScrollNavbar_R0VQ" id="参考资料">参考资料<a class="hash-link" href="#参考资料" title="Direct link to heading"></a></h2><ul><li><a href="https://reactjs.org/docs/reconciliation.html" target="_blank" rel="noopener noreferrer">Reconciliation</a></li><li><a href="https://github.com/vuejs/vue/blob/2.6/src/core/vdom/patch.js" target="_blank" rel="noopener noreferrer">patch</a></li></ul></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages navigation"><div class="pagination-nav__item"><a class="pagination-nav__link" href="/awesome-interview/book3/frame-react-hooks"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">框架:React Hooks 实现原理</div></a></div><div class="pagination-nav__item pagination-nav__item--next"><a class="pagination-nav__link" href="/awesome-interview/book3/js-async"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">基础:JavaScript 异步编程</div></a></div></nav></div></div><div class="col col--3"><div class="tableOfContents_cNA8 thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#相关问题" class="table-of-contents__link toc-highlight">相关问题</a></li><li><a href="#回答关键点" class="table-of-contents__link toc-highlight">回答关键点</a></li><li><a href="#知识点深入" class="table-of-contents__link toc-highlight">知识点深入</a><ul><li><a href="#1-diff-算法" class="table-of-contents__link toc-highlight">1. Diff 算法</a></li><li><a href="#2-react-reconciliation" class="table-of-contents__link toc-highlight">2. React Reconciliation</a></li><li><a href="#2-vue2x-diff" class="table-of-contents__link toc-highlight">2. Vue2.x Diff</a></li></ul></li><li><a href="#参考资料" class="table-of-contents__link toc-highlight">参考资料</a></li></ul></div></div></div><div class="row"><div class="col"><div class="react-utterences"><div>Loading script...</div></div></div><div class="col col--3"></div></div></div></main></div></div></div>
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