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<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 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 information about online/offline status."/><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/blog/atom.xml" title="React Native Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" 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var toggler = document.getElementById('navToggler');
var nav = document.getElementById('docsNav');
toggler.onclick = function() {
nav.classList.toggle('docsSliderActive');
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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">Edit</a><h1>NetInfo</h1></header><article><div><span><p><code>NetInfo</code> exposes information about online/offline status.</p>
<pre><code class="hljs">NetInfo.getConnectionInfo().<span class="hljs-keyword">then</span>((connectionInfo) =&gt; {
console.<span class="hljs-built_in">log</span>(<span class="hljs-string">'Initial, type: '</span> + connectionInfo.<span class="hljs-built_in">type</span> + <span class="hljs-string">', effectiveType: '</span> + connectionInfo.effectiveType);
});
<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">handleFirstConnectivityChange</span><span class="hljs-params">(connectionInfo)</span></span> {
console.<span class="hljs-built_in">log</span>(<span class="hljs-string">'First change, type: '</span> + connectionInfo.<span class="hljs-built_in">type</span> + <span class="hljs-string">', effectiveType: '</span> + connectionInfo.effectiveType);
NetInfo.removeEventListener(
<span class="hljs-string">'connectionChange'</span>,
handleFirstConnectivityChange
);
}
NetInfo.addEventListener(
<span class="hljs-string">'connectionChange'</span>,
handleFirstConnectivityChange
);
</code></pre>
<h3><a class="anchor" aria-hidden="true" name="connectiontype-enum"></a><a href="#connectiontype-enum" aria-hidden="true" class="hash-link" ><svg 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>ConnectionType enum</h3>
<p><code>ConnectionType</code> describes the type of connection the device is using to communicate with the network.</p>
<p>Cross platform values for <code>ConnectionType</code>:</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>cellular</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>
<p>Android-only values for <code>ConnectionType</code>:</p>
<ul>
<li><code>bluetooth</code> - device is connected via Bluetooth</li>
<li><code>ethernet</code> - device is connected via Ethernet</li>
<li><code>wimax</code> - device is connected via WiMAX</li>
</ul>
<h3><a class="anchor" aria-hidden="true" name="effectiveconnectiontype-enum"></a><a href="#effectiveconnectiontype-enum" aria-hidden="true" class="hash-link" ><svg 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>EffectiveConnectionType enum</h3>
<p>Cross platform values for <code>EffectiveConnectionType</code>:</p>
<ul>
<li><code>2g</code></li>
<li><code>3g</code></li>
<li><code>4g</code></li>
<li><code>unknown</code></li>
</ul>
<h3><a class="anchor" aria-hidden="true" name="android"></a><a href="#android" aria-hidden="true" class="hash-link" ><svg 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></p>
<h3><a class="anchor" aria-hidden="true" name="methods"></a><a href="#methods" aria-hidden="true" class="hash-link" ><svg 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/netinfo.html#addeventlistener"><code>addEventListener</code></a></li>
<li><a href="/react-native/docs/netinfo.html#removeeventlistener"><code>removeEventListener</code></a></li>
<li><a href="/react-native/docs/netinfo.html#getconnectioninfo"><code>getConnectionInfo</code></a></li>
<li><a href="/react-native/docs/netinfo.html#isconnectionexpensive"><code>isConnectionExpensive</code></a></li>
</ul>
<h3><a class="anchor" aria-hidden="true" name="properties"></a><a href="#properties" aria-hidden="true" class="hash-link" ><svg 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/netinfo.html#isconnected"><code>isConnected</code></a></li>
</ul>
<hr>
<h1><a class="anchor" aria-hidden="true" name="reference"></a><a href="#reference" aria-hidden="true" class="hash-link" ><svg 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" name="methods"></a><a href="#methods" aria-hidden="true" class="hash-link" ><svg 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" name="addeventlistener"></a><a href="#addeventlistener" aria-hidden="true" class="hash-link" ><svg 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 javascript">NetInfo.addEventListener(eventName, handler);
</code></pre>
<p>Adds an event handler.</p>
<p><strong>Parameters:</strong></p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>eventName</td><td>enum(connectionChange, change)</td><td>Yes</td><td>The change event name.</td></tr>
<tr><td>handler</td><td>function</td><td>Yes</td><td>Listener function.</td></tr>
</tbody>
</table>
<p>Supported events:</p>
<ul>
<li><code>connectionChange</code>: Fires when the network status changes. The argument to the event handler is an object with keys:
<ul>
<li><code>type</code>: A <code>ConnectionType</code> (listed above)</li>
<li><code>effectiveType</code>: An <code>EffectiveConnectionType</code> (listed above)</li>
</ul></li>
<li><code>change</code>: This event is deprecated. Listen to <code>connectionChange</code> instead. Fires when the network status changes. The argument to the event handler is one of the deprecated connectivity types listed above.</li>
</ul>
<hr>
<h3><a class="anchor" aria-hidden="true" name="removeeventlistener"></a><a href="#removeeventlistener" aria-hidden="true" class="hash-link" ><svg 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 javascript">NetInfo.removeEventListener(eventName, handler);
</code></pre>
<p>Removes the listener for network status changes.</p>
<p><strong>Parameters:</strong></p>
<table>
<thead>
<tr><th>Name</th><th>Type</th><th>Required</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td>eventName</td><td>enum(connectionChange, change)</td><td>Yes</td><td>The change event name.</td></tr>
<tr><td>handler</td><td>function</td><td>Yes</td><td>Listener function.</td></tr>
</tbody>
</table>
<hr>
<h3><a class="anchor" aria-hidden="true" name="getconnectioninfo"></a><a href="#getconnectioninfo" aria-hidden="true" class="hash-link" ><svg 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>getConnectionInfo()</code></h3>
<pre><code class="hljs css javascript">NetInfo.getConnectionInfo();
</code></pre>
<p>Returns a promise that resolves to an object with <code>type</code> and <code>effectiveType</code> keys whose values are a <a href="/react-native/docs/netinfo.html#connectiontype-enum"><code>ConnectionType</code></a> and an <a href="/react-native/docs/netinfo.html#effectiveconnectiontype-enum"><code>EffectiveConnectionType</code></a>), respectively.</p>
<hr>
<h3><a class="anchor" aria-hidden="true" name="isconnectionexpensive"></a><a href="#isconnectionexpensive" aria-hidden="true" class="hash-link" ><svg 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 javascript">NetInfo.isConnectionExpensive();
</code></pre>
<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()
.then(<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>));
})
.catch(<span class="hljs-function"><span class="hljs-params">error</span> =&gt;</span> {
<span class="hljs-built_in">console</span>.error(error);
});
</code></pre>
<h2><a class="anchor" aria-hidden="true" name="properties"></a><a href="#properties" aria-hidden="true" class="hash-link" ><svg 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>
<h3><a class="anchor" aria-hidden="true" name="isconnected"></a><a href="#isconnected" aria-hidden="true" class="hash-link" ><svg 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>isConnected</code></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().then(<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">'connectionChange'</span>,
handleFirstConnectivityChange
);
}
NetInfo.<span class="hljs-keyword">isConnected</span>.addEventListener(
<span class="hljs-string">'connectionChange'</span>,
handleFirstConnectivityChange
);
</code></pre>
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