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Ben Alpert
542 lines
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HTML
542 lines
27 KiB
HTML
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<a href="/react/docs/top-level-api.html" class="active">Top-Level API</a>
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<a href="http://facebook.github.io/flux/docs/overview.html">Flux Overview</a>
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<a href="http://facebook.github.io/flux/docs/todo-list.html">Flux TodoMVC Tutorial</a>
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<!-- Tips Nav -->
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<h3>Tips</h3>
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<ul>
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<a href="/react/tips/introduction.html">Introduction</a>
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<a href="/react/tips/inline-styles.html">Inline Styles</a>
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<li>
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<a href="/react/tips/if-else-in-JSX.html">If-Else in JSX</a>
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<li>
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<a href="/react/tips/self-closing-tag.html">Self-Closing Tag</a>
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<li>
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<a href="/react/tips/maximum-number-of-jsx-root-nodes.html">Maximum Number of JSX Root Nodes</a>
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</li>
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<li>
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<a href="/react/tips/style-props-value-px.html">Shorthand for Specifying Pixel Values in style props</a>
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<li>
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<a href="/react/tips/children-props-type.html">Type of the Children props</a>
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<li>
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<a href="/react/tips/controlled-input-null-value.html">Value of null for Controlled Input</a>
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</li>
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<li>
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<a href="/react/tips/componentWillReceiveProps-not-triggered-after-mounting.html">componentWillReceiveProps Not Triggered After Mounting</a>
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</li>
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<li>
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<a href="/react/tips/props-in-getInitialState-as-anti-pattern.html">Props in getInitialState Is an Anti-Pattern</a>
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</li>
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<li>
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<a href="/react/tips/dom-event-listeners.html">DOM Event Listeners in a Component</a>
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</li>
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<li>
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<a href="/react/tips/initial-ajax.html">Load Initial Data via AJAX</a>
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</li>
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<li>
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<a href="/react/tips/false-in-jsx.html">False in JSX</a>
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</li>
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<li>
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<a href="/react/tips/communicate-between-components.html">Communicate Between Components</a>
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</li>
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<li>
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<a href="/react/tips/expose-component-functions.html">Expose Component Functions</a>
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</li>
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<li>
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<a href="/react/tips/references-to-components.html">References to Components</a>
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</li>
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<li>
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<a href="/react/tips/children-undefined.html">this.props.children undefined</a>
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</li>
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<li>
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<a href="/react/tips/use-react-with-other-libraries.html">Use React with Other Libraries</a>
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</li>
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<li>
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<a href="/react/tips/dangerously-set-inner-html.html">Dangerously Set innerHTML</a>
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</li>
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</ul>
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</div>
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</div>
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<div class="inner-content">
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<h1>
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Top-Level API
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<a class="edit-page-link" href="https://github.com/facebook/react/tree/master/docs/docs/ref-01-top-level-api.md" target="_blank">Edit on GitHub</a>
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</h1>
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<div class="subHeader"></div>
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<h2><a class="anchor" name="react"></a>React <a class="hash-link" href="#react">#</a></h2>
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<p><code>React</code> is the entry point to the React library. If you're using one of the prebuilt packages it's available as a global; if you're using CommonJS modules you can <code>require()</code> it.</p>
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<h3><a class="anchor" name="react.component"></a>React.Component <a class="hash-link" href="#react.component">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kr">class</span> <span class="nx">Component</span>
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</code></pre></div>
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<p>This is the base class for React Components when they're defined using ES6 classes. See <a href="/react/docs/reusable-components.html#es6-classes">Reusable Components</a> for how to use ES6 classes with React. For what methods are actually provided by the base class, see the <a href="/react/docs/component-api.html">Component API</a>.</p>
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<h3><a class="anchor" name="react.createclass"></a>React.createClass <a class="hash-link" href="#react.createclass">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">ReactClass</span> <span class="nx">createClass</span><span class="p">(</span><span class="nx">object</span> <span class="nx">specification</span><span class="p">)</span>
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</code></pre></div>
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<p>Create a component class, given a specification. A component implements a <code>render</code> method which returns <strong>one single</strong> child. That child may have an arbitrarily deep child structure. One thing that makes components different than standard prototypal classes is that you don't need to call new on them. They are convenience wrappers that construct backing instances (via new) for you.</p>
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<p>For more information about the specification object, see <a href="/react/docs/component-specs.html">Component Specs and Lifecycle</a>.</p>
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<h3><a class="anchor" name="react.createelement"></a>React.createElement <a class="hash-link" href="#react.createelement">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">ReactElement</span> <span class="nx">createElement</span><span class="p">(</span>
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<span class="nx">string</span><span class="o">/</span><span class="nx">ReactClass</span> <span class="nx">type</span><span class="p">,</span>
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<span class="p">[</span><span class="nx">object</span> <span class="nx">props</span><span class="p">],</span>
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<span class="p">[</span><span class="nx">children</span> <span class="p">...]</span>
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<span class="p">)</span>
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</code></pre></div>
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<p>Create and return a new <code>ReactElement</code> of the given type. The type argument can be either an
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html tag name string (eg. 'div', 'span', etc), or a <code>ReactClass</code> (created via <code>React.createClass</code>).</p>
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<h3><a class="anchor" name="react.cloneelement"></a>React.cloneElement <a class="hash-link" href="#react.cloneelement">#</a></h3><div class="highlight"><pre><code class="language-text" data-lang="text">ReactElement cloneElement(
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ReactElement element,
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[object props],
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[children ...]
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)
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</code></pre></div>
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<p>Clone and return a new <code>ReactElement</code> using <code>element</code> as the starting point. The resulting element will have the original element's props with the new props merged in shallowly. New children will replace existing children. Unlike <code>React.addons.cloneWithProps</code>, <code>key</code> and <code>ref</code> from the original element will be preserved. There is no special behavior for merging any props (unlike <code>cloneWithProps</code>). See the <a href="/react/blog/2015/03/03/react-v0.13-rc2.html">v0.13 RC2 blog post</a> for additional details.</p>
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<h3><a class="anchor" name="react.createfactory"></a>React.createFactory <a class="hash-link" href="#react.createfactory">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">factoryFunction</span> <span class="nx">createFactory</span><span class="p">(</span>
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<span class="nx">string</span><span class="o">/</span><span class="nx">ReactClass</span> <span class="nx">type</span>
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<span class="p">)</span>
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</code></pre></div>
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<p>Return a function that produces ReactElements of a given type. Like <code>React.createElement</code>,
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the type argument can be either an html tag name string (eg. 'div', 'span', etc), or a
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<code>ReactClass</code>.</p>
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<h3><a class="anchor" name="react.render"></a>React.render <a class="hash-link" href="#react.render">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">ReactComponent</span> <span class="nx">render</span><span class="p">(</span>
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<span class="nx">ReactElement</span> <span class="nx">element</span><span class="p">,</span>
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<span class="nx">DOMElement</span> <span class="nx">container</span><span class="p">,</span>
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<span class="p">[</span><span class="kd">function</span> <span class="nx">callback</span><span class="p">]</span>
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<span class="p">)</span>
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</code></pre></div>
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<p>Render a ReactElement into the DOM in the supplied <code>container</code> and return a reference to the component.</p>
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<p>If the ReactElement was previously rendered into <code>container</code>, this will perform an update on it and only mutate the DOM as necessary to reflect the latest React component.</p>
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<p>If the optional callback is provided, it will be executed after the component is rendered or updated.</p>
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<blockquote>
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<p>Note:</p>
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<p><code>React.render()</code> replaces the contents of the container node you
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pass in. In the future, it may be possible to insert a component to an
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existing DOM node without overwriting the existing children.</p>
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</blockquote>
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<h3><a class="anchor" name="react.unmountcomponentatnode"></a>React.unmountComponentAtNode <a class="hash-link" href="#react.unmountcomponentatnode">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kr">boolean</span> <span class="nx">unmountComponentAtNode</span><span class="p">(</span><span class="nx">DOMElement</span> <span class="nx">container</span><span class="p">)</span>
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</code></pre></div>
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<p>Remove a mounted React component from the DOM and clean up its event handlers and state. If no component was mounted in the container, calling this function does nothing. Returns <code>true</code> if a component was unmounted and <code>false</code> if there was no component to unmount.</p>
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<h3><a class="anchor" name="react.rendertostring"></a>React.renderToString <a class="hash-link" href="#react.rendertostring">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">string</span> <span class="nx">renderToString</span><span class="p">(</span><span class="nx">ReactElement</span> <span class="nx">element</span><span class="p">)</span>
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|
</code></pre></div>
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<p>Render a ReactElement to its initial HTML. This should only be used on the server. React will return an HTML string. You can use this method to generate HTML on the server and send the markup down on the initial request for faster page loads and to allow search engines to crawl your pages for SEO purposes.</p>
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<p>If you call <code>React.render()</code> on a node that already has this server-rendered markup, React will preserve it and only attach event handlers, allowing you to have a very performant first-load experience.</p>
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<h3><a class="anchor" name="react.rendertostaticmarkup"></a>React.renderToStaticMarkup <a class="hash-link" href="#react.rendertostaticmarkup">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">string</span> <span class="nx">renderToStaticMarkup</span><span class="p">(</span><span class="nx">ReactElement</span> <span class="nx">element</span><span class="p">)</span>
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</code></pre></div>
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<p>Similar to <code>renderToString</code>, except this doesn't create extra DOM attributes such as <code>data-react-id</code>, that React uses internally. This is useful if you want to use React as a simple static page generator, as stripping away the extra attributes can save lots of bytes.</p>
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<h3><a class="anchor" name="react.isvalidelement"></a>React.isValidElement <a class="hash-link" href="#react.isvalidelement">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="kr">boolean</span> <span class="nx">isValidElement</span><span class="p">(</span><span class="o">*</span> <span class="nx">object</span><span class="p">)</span>
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|
</code></pre></div>
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|
<p>Verifies the object is a ReactElement.</p>
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<h3><a class="anchor" name="react.finddomnode"></a>React.findDOMNode <a class="hash-link" href="#react.finddomnode">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">DOMElement</span> <span class="nx">findDOMNode</span><span class="p">(</span><span class="nx">ReactComponent</span> <span class="nx">component</span><span class="p">)</span>
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|
</code></pre></div>
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|
<p>If this component has been mounted into the DOM, this returns the corresponding native browser DOM element. This method is useful for reading values out of the DOM, such as form field values and performing DOM measurements. When <code>render</code> returns <code>null</code> or <code>false</code>, <code>findDOMNode</code> returns <code>null</code>.</p>
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<h3><a class="anchor" name="react.dom"></a>React.DOM <a class="hash-link" href="#react.dom">#</a></h3>
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<p><code>React.DOM</code> provides convenience wrappers around <code>React.createElement</code> for DOM components. These should only be used when not using JSX. For example, <code>React.DOM.div(null, 'Hello World!')</code></p>
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<h3><a class="anchor" name="react.proptypes"></a>React.PropTypes <a class="hash-link" href="#react.proptypes">#</a></h3>
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<p><code>React.PropTypes</code> includes types that can be used with a component's <code>propTypes</code> object to validate props being passed to your components. For more information about <code>propTypes</code>, see <a href="/react/docs/reusable-components.html">Reusable Components</a>.</p>
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<h3><a class="anchor" name="react.initializetouchevents"></a>React.initializeTouchEvents <a class="hash-link" href="#react.initializetouchevents">#</a></h3><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">initializeTouchEvents</span><span class="p">(</span><span class="kr">boolean</span> <span class="nx">shouldUseTouch</span><span class="p">)</span>
|
|
</code></pre></div>
|
|
<p>Configure React's event system to handle touch events on mobile devices.</p>
|
|
<h3><a class="anchor" name="react.children"></a>React.Children <a class="hash-link" href="#react.children">#</a></h3>
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|
<p><code>React.Children</code> provides utilities for dealing with the <code>this.props.children</code> opaque data structure.</p>
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|
<h4><a class="anchor" name="react.children.map"></a>React.Children.map <a class="hash-link" href="#react.children.map">#</a></h4><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">object</span> <span class="nx">React</span><span class="p">.</span><span class="nx">Children</span><span class="p">.</span><span class="nx">map</span><span class="p">(</span><span class="nx">object</span> <span class="nx">children</span><span class="p">,</span> <span class="kd">function</span> <span class="nx">fn</span> <span class="p">[,</span> <span class="nx">object</span> <span class="nx">context</span><span class="p">])</span>
|
|
</code></pre></div>
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|
<p>Invoke <code>fn</code> on every immediate child contained within <code>children</code> with <code>this</code> set to <code>context</code>. If <code>children</code> is a nested object or array it will be traversed: <code>fn</code> will never be passed the container objects. If children is <code>null</code> or <code>undefined</code> returns <code>null</code> or <code>undefined</code> rather than an empty object.</p>
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|
<h4><a class="anchor" name="react.children.foreach"></a>React.Children.forEach <a class="hash-link" href="#react.children.foreach">#</a></h4><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">React</span><span class="p">.</span><span class="nx">Children</span><span class="p">.</span><span class="nx">forEach</span><span class="p">(</span><span class="nx">object</span> <span class="nx">children</span><span class="p">,</span> <span class="kd">function</span> <span class="nx">fn</span> <span class="p">[,</span> <span class="nx">object</span> <span class="nx">context</span><span class="p">])</span>
|
|
</code></pre></div>
|
|
<p>Like <code>React.Children.map()</code> but does not return an object.</p>
|
|
<h4><a class="anchor" name="react.children.count"></a>React.Children.count <a class="hash-link" href="#react.children.count">#</a></h4><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">number</span> <span class="nx">React</span><span class="p">.</span><span class="nx">Children</span><span class="p">.</span><span class="nx">count</span><span class="p">(</span><span class="nx">object</span> <span class="nx">children</span><span class="p">)</span>
|
|
</code></pre></div>
|
|
<p>Return the total number of components in <code>children</code>, equal to the number of times that a callback passed to <code>map</code> or <code>forEach</code> would be invoked.</p>
|
|
<h4><a class="anchor" name="react.children.only"></a>React.Children.only <a class="hash-link" href="#react.children.only">#</a></h4><div class="highlight"><pre><code class="language-javascript" data-lang="javascript"><span class="nx">object</span> <span class="nx">React</span><span class="p">.</span><span class="nx">Children</span><span class="p">.</span><span class="nx">only</span><span class="p">(</span><span class="nx">object</span> <span class="nx">children</span><span class="p">)</span>
|
|
</code></pre></div>
|
|
<p>Return the only child in <code>children</code>. Throws otherwise.</p>
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