mirror of
https://github.com/facebook/react.git
synced 2025-11-01 09:12:30 +00:00
Travis CI
582 lines
28 KiB
HTML
582 lines
28 KiB
HTML
<!DOCTYPE html>
|
|
<!--[if IE]><![endif]-->
|
|
<html>
|
|
<head>
|
|
<meta charset="utf-8">
|
|
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
|
|
<title>React (Virtual) DOM Terminology | React</title>
|
|
<meta name="viewport" content="width=device-width">
|
|
<meta property="og:title" content="React (Virtual) DOM Terminology | React">
|
|
<meta property="og:type" content="website">
|
|
<meta property="og:url" content="https://facebook.github.io/react/docs/glossary.html">
|
|
<meta property="og:image" content="https://facebook.github.io/react/img/logo_og.png">
|
|
<meta property="og:description" content="A JavaScript library for building user interfaces">
|
|
<meta property="fb:app_id" content="623268441017527">
|
|
|
|
<link rel="shortcut icon" href="/react/favicon.ico">
|
|
<link rel="alternate" type="application/rss+xml" title="React" href="https://facebook.github.io/react/feed.xml">
|
|
|
|
<link rel="stylesheet" href="/react/css/syntax.css">
|
|
<link rel="stylesheet" href="/react/css/codemirror.css">
|
|
<link rel="stylesheet" href="/react/css/react.css">
|
|
|
|
<script type="text/javascript" src="//use.typekit.net/vqa1hcx.js"></script>
|
|
<script type="text/javascript">try{Typekit.load();}catch(e){}</script>
|
|
|
|
<!--[if lte IE 8]>
|
|
<script type="text/javascript" src="/react/js/html5shiv.min.js"></script>
|
|
<script type="text/javascript" src="/react/js/es5-shim.min.js"></script>
|
|
<script type="text/javascript" src="/react/js/es5-sham.min.js"></script>
|
|
<![endif]-->
|
|
<script type="text/javascript" src="/react/js/codemirror.js"></script>
|
|
<script type="text/javascript" src="/react/js/javascript.js"></script>
|
|
<script type="text/javascript" src="/react/js/react.js"></script>
|
|
<script type="text/javascript" src="/react/js/JSXTransformer.js"></script>
|
|
<script type="text/javascript" src="/react/js/live_editor.js"></script>
|
|
</head>
|
|
<body>
|
|
|
|
<div class="container">
|
|
|
|
<div class="nav-main">
|
|
<div class="wrap">
|
|
<a class="nav-home" href="/react/index.html">
|
|
<img class="nav-logo" src="/react/img/logo.svg" width="36" height="36">
|
|
React
|
|
</a>
|
|
<ul class="nav-site nav-site-internal">
|
|
<li><a href="/react/docs/getting-started.html" class="active">Docs</a></li>
|
|
<li><a href="/react/support.html">Support</a></li>
|
|
<li><a href="/react/downloads.html">Download</a></li>
|
|
<li><a href="/react/blog/">Blog</a></li>
|
|
</ul>
|
|
|
|
<ul class="nav-site nav-site-external">
|
|
<li><a href="https://github.com/facebook/react">GitHub</a>
|
|
<li><a href="https://facebook.github.io/react-native/">React Native</a>
|
|
</ul>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
<section class="content wrap documentationContent">
|
|
<div class="nav-docs">
|
|
<!-- Docs Nav -->
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Quick Start</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/getting-started.html">Getting Started</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/tutorial.html">Tutorial</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/thinking-in-react.html">Thinking in React</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Community Resources</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/conferences.html">Conferences</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/videos.html">Videos</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/complementary-tools.html">Complementary Tools</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/examples.html">Examples</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Guides</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/why-react.html">Why React?</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/displaying-data.html">Displaying Data</a>
|
|
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/jsx-in-depth.html">JSX in Depth</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/jsx-spread.html">JSX Spread Attributes</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/jsx-gotchas.html">JSX Gotchas</a>
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/interactivity-and-dynamic-uis.html">Interactivity and Dynamic UIs</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/multiple-components.html">Multiple Components</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/reusable-components.html">Reusable Components</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/transferring-props.html">Transferring Props</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/forms.html">Forms</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/working-with-the-browser.html">Working With the Browser</a>
|
|
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/more-about-refs.html">More About Refs</a>
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/tooling-integration.html">Tooling Integration</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/addons.html">Add-Ons</a>
|
|
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/animation.html">Animation</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/two-way-binding-helpers.html">Two-Way Binding Helpers</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/class-name-manipulation.html">Class Name Manipulation</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/test-utils.html">Test Utilities</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/clone-with-props.html">Cloning Elements</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/create-fragment.html">Keyed Fragments</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/update.html">Immutability Helpers</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/pure-render-mixin.html">PureRenderMixin</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/perf.html">Performance Tools</a>
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/advanced-performance.html">Advanced Performance</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Reference</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/docs/top-level-api.html">Top-Level API</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/component-api.html">Component API</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/component-specs.html">Component Specs and Lifecycle</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/tags-and-attributes.html">Supported Tags and Attributes</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/events.html">Event System</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/dom-differences.html">DOM Differences</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/special-non-dom-attributes.html">Special Non-DOM Attributes</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/reconciliation.html">Reconciliation</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/docs/glossary.html" class="active">React (Virtual) DOM Terminology</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Flux</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="https://facebook.github.io/flux/docs/overview.html">Flux Overview</a>
|
|
|
|
</li>
|
|
|
|
<li>
|
|
<a href="https://facebook.github.io/flux/docs/todo-list.html">Flux TodoMVC Tutorial</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
|
|
<!-- Tips Nav -->
|
|
|
|
<div class="nav-docs-section">
|
|
<h3>Tips</h3>
|
|
<ul>
|
|
|
|
<li>
|
|
<a href="/react/tips/introduction.html">Introduction</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/inline-styles.html">Inline Styles</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/if-else-in-JSX.html">If-Else in JSX</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/self-closing-tag.html">Self-Closing Tag</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/maximum-number-of-jsx-root-nodes.html">Maximum Number of JSX Root Nodes</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/style-props-value-px.html">Shorthand for Specifying Pixel Values in style props</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/children-props-type.html">Type of the Children props</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/controlled-input-null-value.html">Value of null for Controlled Input</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/componentWillReceiveProps-not-triggered-after-mounting.html">componentWillReceiveProps Not Triggered After Mounting</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/props-in-getInitialState-as-anti-pattern.html">Props in getInitialState Is an Anti-Pattern</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/dom-event-listeners.html">DOM Event Listeners in a Component</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/initial-ajax.html">Load Initial Data via AJAX</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/false-in-jsx.html">False in JSX</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/communicate-between-components.html">Communicate Between Components</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/expose-component-functions.html">Expose Component Functions</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/references-to-components.html">References to Components</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/children-undefined.html">this.props.children undefined</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/use-react-with-other-libraries.html">Use React with Other Libraries</a>
|
|
</li>
|
|
|
|
<li>
|
|
<a href="/react/tips/dangerously-set-inner-html.html">Dangerously Set innerHTML</a>
|
|
</li>
|
|
|
|
</ul>
|
|
</div>
|
|
|
|
</div>
|
|
|
|
|
|
<div class="inner-content">
|
|
<h1>
|
|
React (Virtual) DOM Terminology
|
|
<a class="edit-page-link" href="https://github.com/facebook/react/tree/master/docs/docs/ref-09-glossary.md" target="_blank">Edit on GitHub</a>
|
|
</h1>
|
|
<div class="subHeader"></div>
|
|
|
|
<p>In React's terminology, there are five core types that are important to distinguish:</p>
|
|
|
|
<ul>
|
|
<li><a href="#react-elements">ReactElement / ReactElement Factory</a></li>
|
|
<li><a href="#react-nodes">ReactNode</a></li>
|
|
<li><a href="#react-components">ReactComponent / ReactComponent Class</a></li>
|
|
</ul>
|
|
<h2><a class="anchor" name="react-elements"></a>React Elements <a class="hash-link" href="#react-elements">#</a></h2>
|
|
<p>The primary type in React is the <code>ReactElement</code>. It has four properties: <code>type</code>, <code>props</code>, <code>key</code> and <code>ref</code>. It has no methods and nothing on the prototype.</p>
|
|
|
|
<p>You can create one of these objects through <code>React.createElement</code>.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createElement</span><span class="p">(</span><span class="s1">'div'</span><span class="p">);</span>
|
|
</code></pre></div>
|
|
<p>To render a new tree into the DOM, you create <code>ReactElement</code>s and pass them to <code>React.render</code> along with a regular DOM <code>Element</code> (<code>HTMLElement</code> or <code>SVGElement</code>). <code>ReactElement</code>s are not to be confused with DOM <code>Element</code>s. A <code>ReactElement</code> is a light, stateless, immutable, virtual representation of a DOM <code>Element</code>. It is a virtual DOM.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="nx">root</span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
</code></pre></div>
|
|
<p>To add properties to a DOM element, pass a properties object as the second argument and children to the third argument.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">child</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createElement</span><span class="p">(</span><span class="s1">'li'</span><span class="p">,</span> <span class="kc">null</span><span class="p">,</span> <span class="s1">'Text Content'</span><span class="p">);</span>
|
|
<span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createElement</span><span class="p">(</span><span class="s1">'ul'</span><span class="p">,</span> <span class="p">{</span> <span class="nx">className</span><span class="o">:</span> <span class="s1">'my-list'</span> <span class="p">},</span> <span class="nx">child</span><span class="p">);</span>
|
|
<span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="nx">root</span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
</code></pre></div>
|
|
<p>If you use React JSX, then these <code>ReactElement</code>s are created for you. So this is equivalent:</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="o"><</span><span class="nx">ul</span> <span class="nx">className</span><span class="o">=</span><span class="s2">"my-list"</span><span class="o">></span>
|
|
<span class="o"><</span><span class="nx">li</span><span class="o">></span><span class="nx">Text</span> <span class="nx">Content</span><span class="o"><</span><span class="err">/li></span>
|
|
<span class="o"><</span><span class="err">/ul>;</span>
|
|
<span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="nx">root</span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
</code></pre></div>
|
|
<p><strong>Factories</strong></p>
|
|
|
|
<p>A <code>ReactElement</code>-factory is simply a function that generates a <code>ReactElement</code> with a particular <code>type</code> property. React has a built-in helper for you to create factories. It's effectively just:</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">function</span> <span class="nx">createFactory</span><span class="p">(</span><span class="nx">type</span><span class="p">)</span> <span class="p">{</span>
|
|
<span class="k">return</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createElement</span><span class="p">.</span><span class="nx">bind</span><span class="p">(</span><span class="kc">null</span><span class="p">,</span> <span class="nx">type</span><span class="p">);</span>
|
|
<span class="p">}</span>
|
|
</code></pre></div>
|
|
<p>It allows you to create a convenient short-hand instead of typing out <code>React.createElement('div')</code> all the time.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">div</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createFactory</span><span class="p">(</span><span class="s1">'div'</span><span class="p">);</span>
|
|
<span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="nx">div</span><span class="p">({</span> <span class="nx">className</span><span class="o">:</span> <span class="s1">'my-div'</span> <span class="p">});</span>
|
|
<span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="nx">root</span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
</code></pre></div>
|
|
<p>React already has built-in factories for common HTML tags:</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">root</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">DOM</span><span class="p">.</span><span class="nx">ul</span><span class="p">({</span> <span class="nx">className</span><span class="o">:</span> <span class="s1">'my-list'</span> <span class="p">},</span>
|
|
<span class="nx">React</span><span class="p">.</span><span class="nx">DOM</span><span class="p">.</span><span class="nx">li</span><span class="p">(</span><span class="kc">null</span><span class="p">,</span> <span class="s1">'Text Content'</span><span class="p">)</span>
|
|
<span class="p">);</span>
|
|
</code></pre></div>
|
|
<p>If you are using JSX you have no need for factories. JSX already provides a convenient short-hand for creating <code>ReactElement</code>s.</p>
|
|
<h2><a class="anchor" name="react-nodes"></a>React Nodes <a class="hash-link" href="#react-nodes">#</a></h2>
|
|
<p>A <code>ReactNode</code> can be either:</p>
|
|
|
|
<ul>
|
|
<li><code>ReactElement</code></li>
|
|
<li><code>string</code> (aka <code>ReactText</code>)</li>
|
|
<li><code>number</code> (aka <code>ReactText</code>)</li>
|
|
<li>Array of <code>ReactNode</code>s (aka <code>ReactFragment</code>)</li>
|
|
</ul>
|
|
|
|
<p>These are used as properties of other <code>ReactElement</code>s to represent children. Effectively they create a tree of <code>ReactElement</code>s.</p>
|
|
<h2><a class="anchor" name="react-components"></a>React Components <a class="hash-link" href="#react-components">#</a></h2>
|
|
<p>You can use React using only <code>ReactElement</code>s but to really take advantage of React, you'll want to use <code>ReactComponent</code>s to create encapsulations with embedded state.</p>
|
|
|
|
<p>A <code>ReactComponent</code> Class is simply just a JavaScript class (or "constructor function").</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">MyComponent</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createClass</span><span class="p">({</span>
|
|
<span class="nx">render</span><span class="o">:</span> <span class="kd">function</span><span class="p">()</span> <span class="p">{</span>
|
|
<span class="p">...</span>
|
|
<span class="p">}</span>
|
|
<span class="p">});</span>
|
|
</code></pre></div>
|
|
<p>When this constructor is invoked it is expected to return an object with at least a <code>render</code> method on it. This object is referred to as a <code>ReactComponent</code>.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">component</span> <span class="o">=</span> <span class="k">new</span> <span class="nx">MyComponent</span><span class="p">(</span><span class="nx">props</span><span class="p">);</span> <span class="c1">// never do this</span>
|
|
</code></pre></div>
|
|
<p>Other than for testing, you would normally <strong>never</strong> call this constructor yourself. React calls it for you.</p>
|
|
|
|
<p>Instead, you pass the <code>ReactComponent</code> Class to <code>createElement</code> you get a <code>ReactElement</code>.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">element</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">createElement</span><span class="p">(</span><span class="nx">MyComponent</span><span class="p">);</span>
|
|
</code></pre></div>
|
|
<p>OR using JSX:</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">element</span> <span class="o">=</span> <span class="o"><</span><span class="nx">MyComponent</span> <span class="o">/></span><span class="p">;</span>
|
|
</code></pre></div>
|
|
<p>When this is passed to <code>React.render</code>, React will call the constructor for you and create a <code>ReactComponent</code>, which returned.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">component</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="nx">element</span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
</code></pre></div>
|
|
<p>If you keep calling <code>React.render</code> with the same type of <code>ReactElement</code> and the same container DOM <code>Element</code> it always returns the same instance. This instance is stateful.</p>
|
|
<div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kd">var</span> <span class="nx">componentA</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="o"><</span><span class="nx">MyComponent</span> <span class="o">/></span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
<span class="kd">var</span> <span class="nx">componentB</span> <span class="o">=</span> <span class="nx">React</span><span class="p">.</span><span class="nx">render</span><span class="p">(</span><span class="o"><</span><span class="nx">MyComponent</span> <span class="o">/></span><span class="p">,</span> <span class="nb">document</span><span class="p">.</span><span class="nx">getElementById</span><span class="p">(</span><span class="s1">'example'</span><span class="p">));</span>
|
|
<span class="nx">componentA</span> <span class="o">===</span> <span class="nx">componentB</span><span class="p">;</span> <span class="c1">// true</span>
|
|
</code></pre></div>
|
|
<p>This is why you shouldn't construct your own instance. Instead, <code>ReactElement</code> is a virtual <code>ReactComponent</code> before it gets constructed. An old and new <code>ReactElement</code> can be compared to see if a new <code>ReactComponent</code> instance is created or if the existing one is reused.</p>
|
|
|
|
<p>The <code>render</code> method of a <code>ReactComponent</code> is expected to return another <code>ReactElement</code>. This allows these components to be composed. Ultimately the render resolves into <code>ReactElement</code> with a <code>string</code> tag which instantiates a DOM <code>Element</code> instance and inserts it into the document.</p>
|
|
<h2><a class="anchor" name="formal-type-definitions"></a>Formal Type Definitions <a class="hash-link" href="#formal-type-definitions">#</a></h2>
|
|
<p><strong>Entry Point</strong></p>
|
|
<div class="highlight"><pre><code class="language-text" data-lang="text">React.render = (ReactElement, HTMLElement | SVGElement) => ReactComponent;
|
|
</code></pre></div>
|
|
<p><strong>Nodes and Elements</strong></p>
|
|
<div class="highlight"><pre><code class="language-text" data-lang="text">type ReactNode = ReactElement | ReactFragment | ReactText;
|
|
|
|
type ReactElement = ReactComponentElement | ReactDOMElement;
|
|
|
|
type ReactDOMElement = {
|
|
type : string,
|
|
props : {
|
|
children : ReactNodeList,
|
|
className : string,
|
|
etc.
|
|
},
|
|
key : string | boolean | number | null,
|
|
ref : string | null
|
|
};
|
|
|
|
type ReactComponentElement<TProps> = {
|
|
type : ReactClass<TProps>,
|
|
props : TProps,
|
|
key : string | boolean | number | null,
|
|
ref : string | null
|
|
};
|
|
|
|
type ReactFragment = Array<ReactNode | ReactEmpty>;
|
|
|
|
type ReactNodeList = ReactNode | ReactEmpty;
|
|
|
|
type ReactText = string | number;
|
|
|
|
type ReactEmpty = null | undefined | boolean;
|
|
</code></pre></div>
|
|
<p><strong>Classes and Components</strong></p>
|
|
<div class="highlight"><pre><code class="language-text" data-lang="text">type ReactClass<TProps> = (TProps) => ReactComponent<TProps>;
|
|
|
|
type ReactComponent<TProps> = {
|
|
props : TProps,
|
|
render : () => ReactElement
|
|
};
|
|
</code></pre></div>
|
|
|
|
<div class="docs-prevnext">
|
|
|
|
<a class="docs-prev" href="/react/docs/reconciliation.html">← Prev</a>
|
|
|
|
|
|
</div>
|
|
</div>
|
|
</section>
|
|
|
|
|
|
<footer class="wrap">
|
|
<div class="left">
|
|
A Facebook & Instagram collaboration.<br>
|
|
<a href="/react/acknowledgements.html">Acknowledgements</a>
|
|
</div>
|
|
<div class="right">
|
|
© 2013–2015 Facebook Inc.<br>
|
|
Documentation licensed under <a href="https://creativecommons.org/licenses/by/4.0/">CC BY 4.0</a>.
|
|
</div>
|
|
</footer>
|
|
</div>
|
|
<div id="fb-root"></div>
|
|
|
|
<script>
|
|
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
|
|
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
|
|
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
|
|
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
|
|
ga('create', 'UA-41298772-1', 'facebook.github.io');
|
|
ga('send', 'pageview');
|
|
|
|
!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="https://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");
|
|
|
|
(function(d, s, id) {
|
|
var js, fjs = d.getElementsByTagName(s)[0];
|
|
if (d.getElementById(id)) return;
|
|
js = d.createElement(s); js.id = id;
|
|
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1&appId=623268441017527";
|
|
fjs.parentNode.insertBefore(js, fjs);
|
|
}(document, 'script', 'facebook-jssdk'));
|
|
</script>
|
|
</body>
|
|
</html>
|