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<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>NetInfo · React Native</title><meta name="viewport" content="width=device-width"/><meta name="generator" content="Docusaurus"/><meta name="description" content="NetInfo exposes info about online/offline status"/><meta name="docsearch:version" content="0.21"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="NetInfo · React Native"/><meta property="og:type" content="website"/><meta property="og:url" content="https://facebook.github.io/react-native/index.html"/><meta property="og:description" content="NetInfo exposes info about online/offline status"/><meta name="twitter:card" content="summary"/><link rel="shortcut icon" href="/react-native/img/favicon.png"/><link rel="stylesheet" href="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.css"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/solarized-dark.min.css"/><link rel="alternate" type="application/atom+xml" href="https://facebook.github.io/react-native/blog/atom.xml" title="React Native Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://facebook.github.io/react-native/blog/feed.xml" title="React Native Blog RSS Feed"/><script>
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href="/react-native/docs/0.21/linking">Linking</a></li><li class="navListItem navListItemActive"><a class="navItem" href="/react-native/docs/0.21/netinfo">NetInfo</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/pixelratio">PixelRatio</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/pushnotificationios">PushNotificationIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/settings">Settings</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/shadow-props">Shadow Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/statusbarios">StatusBarIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/stylesheet">StyleSheet</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.21/text-style-props">Text Style Props</a></li><li class="navListItem"><a class="navItem" 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</script></nav></div><div class="container mainContainer"><div class="wrapper"><div class="post"><header class="postHeader"><a class="edit-page-link button" href="https://github.com/facebook/react-native-website/blob/master/docs/netinfo.md" target="_blank" rel="noreferrer noopener">Edit</a><h1 class="postHeaderTitle">NetInfo</h1></header><article><div><span><p>NetInfo exposes info about online/offline status</p>
<pre><code class="hljs">NetInfo.fetch().done(<span class="hljs-function">(<span class="hljs-params">reach</span>) =&gt;</span> {
<span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Initial: '</span> + reach);
});
<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">handleFirstConnectivityChange</span>(<span class="hljs-params">reach</span>) </span>{
<span class="hljs-built_in">console</span>.log(<span class="hljs-string">'First change: '</span> + reach);
NetInfo.removeEventListener(
<span class="hljs-string">'change'</span>,
handleFirstConnectivityChange
);
}
NetInfo.addEventListener(
<span class="hljs-string">'change'</span>,
handleFirstConnectivityChange
);
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="ios"></a><a href="#ios" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>IOS</h3>
<p>Asynchronously determine if the device is online and on a cellular network.</p>
<ul>
<li><code>none</code> - device is offline</li>
<li><code>wifi</code> - device is online and connected via wifi, or is the iOS simulator</li>
<li><code>cell</code> - device is connected via Edge, 3G, WiMax, or LTE</li>
<li><code>unknown</code> - error case and the network status is unknown</li>
</ul>
<h3><a class="anchor" aria-hidden="true" id="android"></a><a href="#android" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Android</h3>
<p>To request network info, you need to add the following line to your app's <code>AndroidManifest.xml</code>:</p>
<p><code>&lt;uses-permission android:name=&quot;android.permission.ACCESS_NETWORK_STATE&quot; /&gt;</code> Asynchronously determine if the device is connected and details about that connection.</p>
<p>Android Connectivity Types.</p>
<ul>
<li><code>NONE</code> - device is offline</li>
<li><code>BLUETOOTH</code> - The Bluetooth data connection.</li>
<li><code>DUMMY</code> - Dummy data connection.</li>
<li><code>ETHERNET</code> - The Ethernet data connection.</li>
<li><code>MOBILE</code> - The Mobile data connection.</li>
<li><code>MOBILE_DUN</code> - A DUN-specific Mobile data connection.</li>
<li><code>MOBILE_HIPRI</code> - A High Priority Mobile data connection.</li>
<li><code>MOBILE_MMS</code> - An MMS-specific Mobile data connection.</li>
<li><code>MOBILE_SUPL</code> - A SUPL-specific Mobile data connection.</li>
<li><code>VPN</code> - A virtual network using one or more native bearers. Requires API Level 21</li>
<li><code>WIFI</code> - The WIFI data connection.</li>
<li><code>WIMAX</code> - The WiMAX data connection.</li>
<li><code>UNKNOWN</code> - Unknown data connection.</li>
</ul>
<p>The rest ConnectivityStates are hidden by the Android API, but can be used if necessary.</p>
<h3><a class="anchor" aria-hidden="true" id="isconnectionexpensive"></a><a href="#isconnectionexpensive" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>isConnectionExpensive</h3>
<p>Available on Android. Detect if the current active connection is metered or not. A network is classified as metered when the user is sensitive to heavy data usage on that connection due to monetary costs, data limitations or battery/performance issues.</p>
<pre><code class="hljs">NetInfo.isConnectionExpensive(<span class="hljs-function"><span class="hljs-params">(isConnectionExpensive)</span> =&gt;</span> {
<span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Connection is '</span> + (isConnectionExpensive ? <span class="hljs-string">'Expensive'</span> : <span class="hljs-string">'Not Expensive'</span>));
});
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="isconnected"></a><a href="#isconnected" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>isConnected</h3>
<p>Available on all platforms. Asynchronously fetch a boolean to determine internet connectivity.</p>
<pre><code class="hljs">NetInfo.<span class="hljs-keyword">isConnected</span>.fetch().done((<span class="hljs-keyword">isConnected</span>) =&gt; {
console.<span class="hljs-keyword">log</span>(<span class="hljs-string">'First, is '</span> + (<span class="hljs-keyword">isConnected</span> ? <span class="hljs-string">'online'</span> : <span class="hljs-string">'offline'</span>));
});
function handleFirstConnectivityChange(<span class="hljs-keyword">isConnected</span>) {
console.<span class="hljs-keyword">log</span>(<span class="hljs-string">'Then, is '</span> + (<span class="hljs-keyword">isConnected</span> ? <span class="hljs-string">'online'</span> : <span class="hljs-string">'offline'</span>));
NetInfo.<span class="hljs-keyword">isConnected</span>.removeEventListener(
<span class="hljs-string">'change'</span>,
handleFirstConnectivityChange
);
}
NetInfo.<span class="hljs-keyword">isConnected</span>.addEventListener(
<span class="hljs-string">'change'</span>,
handleFirstConnectivityChange
);
</code></pre>
<h3><a class="anchor" aria-hidden="true" id="methods"></a><a href="#methods" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Methods</h3>
<ul>
<li><a href="/react-native/docs/0.21/netinfo#addeventlistener"><code>addEventListener</code></a></li>
<li><a href="/react-native/docs/0.21/netinfo#removeeventlistener"><code>removeEventListener</code></a></li>
<li><a href="/react-native/docs/0.21/netinfo#fetch"><code>fetch</code></a></li>
<li><a href="/react-native/docs/0.21/netinfo#isconnectionexpensive"><code>isConnectionExpensive</code></a></li>
</ul>
<h3><a class="anchor" aria-hidden="true" id="properties"></a><a href="#properties" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Properties</h3>
<ul>
<li><a href="/react-native/docs/0.21/netinfo#isconnected"><code>isConnected</code></a></li>
</ul>
<hr>
<h1><a class="anchor" aria-hidden="true" id="reference"></a><a href="#reference" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Reference</h1>
<h2><a class="anchor" aria-hidden="true" id="methods-1"></a><a href="#methods-1" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Methods</h2>
<h3><a class="anchor" aria-hidden="true" id="addeventlistener"></a><a href="#addeventlistener" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a><code>addEventListener()</code></h3>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">static</span> addEventListener(eventName, handler)
</code></pre>
<hr>
<h3><a class="anchor" aria-hidden="true" id="removeeventlistener"></a><a href="#removeeventlistener" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a><code>removeEventListener()</code></h3>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">static</span> removeEventListener(eventName, handler)
</code></pre>
<hr>
<h3><a class="anchor" aria-hidden="true" id="fetch"></a><a href="#fetch" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a><code>fetch()</code></h3>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">static</span> fetch()
</code></pre>
<hr>
<h3><a class="anchor" aria-hidden="true" id="isconnectionexpensive-1"></a><a href="#isconnectionexpensive-1" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a><code>isConnectionExpensive()</code></h3>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">static</span> isConnectionExpensive(callback)
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="properties-1"></a><a href="#properties-1" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Properties</h2>
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