Facebook/react-native
1
0
Fork 0
mirror of https://github.com/facebook/react-native.git synced 2025-11-01 09:14:26 +00:00
Code Issues Packages Projects Releases Wiki Activity
Files
84a39ade9608994ef4b3151e9d72fe43fdafef3f
react-native/docs/0.49/network.html
T
Website Deployment Script 21dd0d0ee0 Deploy website 
Deploy website version based on 1fe93f5783
2018-06-25 23:27:10 +00:00

206 lines
40 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Networking · React Native</title><meta name="viewport" content="width=device-width"/><meta name="generator" content="Docusaurus"/><meta name="description" content="Many mobile apps need to load resources from a remote URL. You may want to make a POST request to a REST API, or you may simply need to fetch a chunk of static content from another server."/><meta name="docsearch:version" content="0.49"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Networking · 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="Many mobile apps need to load resources from a remote URL. You may want to make a POST request to a REST API, or you may simply need to fetch a chunk of static content from another server."/><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>
(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','https://www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-41298772-2', 'auto');
ga('send', 'pageview');
</script><script type="text/javascript" src="https://snack.expo.io/embed.js"></script><script type="text/javascript" src="/react-native/js/codeblocks.js"></script><link rel="stylesheet" href="/react-native/css/main.css"/></head><body class="sideNavVisible"><div class="fixedHeaderContainer"><div class="headerWrapper wrapper"><header><a href="/react-native/"><img class="logo" src="/react-native/img/header_logo.png" alt="React Native"/><h2 class="headerTitleWithLogo">React Native</h2></a><a href="/react-native/versions"><h3>0.49</h3></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li class="siteNavGroupActive"><a href="/react-native/docs/0.49/getting-started" target="_self">Docs</a></li><li class=""><a href="/react-native/en/help" target="_self">Community</a></li><li class=""><a href="/react-native/blog" target="_self">Blog</a></li><li class="navSearchWrapper reactNavSearchWrapper"><input type="text" id="search_input_react" placeholder="Search" title="Search"/></li><li class=""><a href="https://github.com/facebook/react-native" target="_self">GitHub</a></li><li class=""><a href="https://reactjs.org/" target="_self">React</a></li></ul></nav></div></header></div></div><div class="navPusher"><div class="docMainWrapper wrapper"><div class="container docsNavContainer" id="docsNav"><nav class="toc"><div class="toggleNav"><section class="navWrapper wrapper"><div class="navBreadcrumb wrapper"><div class="navToggle" id="navToggler"><i></i></div><h2><i>›</i><span>The Basics</span></h2></div><div class="navGroups"><div class="navGroup"><h3 class="navGroupCategoryTitle">The Basics</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/getting-started">Getting Started</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/tutorial">Learn the Basics</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/props">Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/state">State</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/style">Style</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/height-and-width">Height and Width</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/flexbox">Layout with Flexbox</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/handling-text-input">Handling Text Input</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/handling-touches">Handling Touches</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/using-a-scrollview">Using a ScrollView</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/using-a-listview">Using List Views</a></li><li class="navListItem navListItemActive"><a class="navItem" href="/react-native/docs/0.49/network">Networking</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/more-resources">More Resources</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Guides</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/components-and-apis">Components and APIs</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/platform-specific-code">Platform Specific Code</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/navigation">Navigating Between Screens</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/images">Images</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/animations">Animations</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/accessibility">Accessibility</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/improvingux">Improving User Experience</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/timers">Timers</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/debugging">Debugging</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/performance">Performance</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/gesture-responder-system">Gesture Responder System</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/javascript-environment">JavaScript Environment</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/direct-manipulation">Direct Manipulation</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/colors">Color Reference</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/integration-with-existing-apps">Integration with Existing Apps</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/running-on-device">Running On Device</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/upgrading">Upgrading to new React Native versions</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/troubleshooting">Troubleshooting</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Guides (iOS)</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/native-modules-ios">Native Modules</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/native-components-ios">Native UI Components</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/linking-libraries-ios">Linking Libraries</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/running-on-simulator-ios">Running On Simulator</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/communication-ios">Communication between native and React Native</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/building-for-apple-tv">Building For TV Devices</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/app-extensions">App Extensions</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Guides (Android)</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/native-modules-android">Native Modules</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/native-components-android">Native UI Components</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/headless-js-android">Headless JS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/signed-apk-android">Generating Signed APK</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Contributing</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/contributing">How to Contribute</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/maintainers">What to Expect from Maintainers</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/building-from-source">Building React Native from source</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/testing">Testing your Changes</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/understanding-cli">Understanding the CLI</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Components</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/activityindicator">ActivityIndicator</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/button">Button</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/datepickerios">DatePickerIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/drawerlayoutandroid">DrawerLayoutAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/flatlist">FlatList</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/image">Image</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/keyboardavoidingview">KeyboardAvoidingView</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/listview">ListView</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/maskedviewios">MaskedViewIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/modal">Modal</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/navigatorios">NavigatorIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/picker">Picker</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/pickerios">PickerIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/progressbarandroid">ProgressBarAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/progressviewios">ProgressViewIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/refreshcontrol">RefreshControl</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/scrollview">ScrollView</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/sectionlist">SectionList</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/segmentedcontrolios">SegmentedControlIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/slider">Slider</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/snapshotviewios">SnapshotViewIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/statusbar">StatusBar</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/switch">Switch</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/tabbarios">TabBarIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/tabbarios-item">TabBarIOS.Item</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/text">Text</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/textinput">TextInput</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/toolbarandroid">ToolbarAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/touchablehighlight">TouchableHighlight</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/touchablenativefeedback">TouchableNativeFeedback</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/touchableopacity">TouchableOpacity</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/touchablewithoutfeedback">TouchableWithoutFeedback</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/view">View</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/viewpagerandroid">ViewPagerAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/virtualizedlist">VirtualizedList</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/webview">WebView</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">APIs</h3><ul><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/accessibilityinfo">AccessibilityInfo</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/actionsheetios">ActionSheetIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/alert">Alert</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/alertios">AlertIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/animated">Animated</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/appregistry">AppRegistry</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/appstate">AppState</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/asyncstorage">AsyncStorage</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/backandroid">BackAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/backhandler">BackHandler</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/cameraroll">CameraRoll</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/clipboard">Clipboard</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/datepickerandroid">DatePickerAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/dimensions">Dimensions</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/easing">Easing</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/geolocation">Geolocation</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/imageeditor">ImageEditor</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/imagepickerios">ImagePickerIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/imagestore">ImageStore</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/image-style-props">Image Style Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/interactionmanager">InteractionManager</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/keyboard">Keyboard</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/layout-props">Layout Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/layoutanimation">LayoutAnimation</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/linking">Linking</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/listviewdatasource">ListViewDataSource</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/netinfo">NetInfo</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/panresponder">PanResponder</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/permissionsandroid">PermissionsAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/pixelratio">PixelRatio</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/pushnotificationios">PushNotificationIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/settings">Settings</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/shadow-props">Shadow Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/share">Share</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/statusbarios">StatusBarIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/stylesheet">StyleSheet</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/systrace">Systrace</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/text-style-props">Text Style Props</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/timepickerandroid">TimePickerAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/toastandroid">ToastAndroid</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/transforms">Transforms</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/vibration">Vibration</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/vibrationios">VibrationIOS</a></li><li class="navListItem"><a class="navItem" href="/react-native/docs/0.49/view-style-props">View Style Props</a></li></ul></div></div></section></div><script>
document.addEventListener('DOMContentLoaded', function() {
createToggler('#navToggler', '#docsNav', 'docsSliderActive');
createToggler('#tocToggler', 'body', 'tocActive');
const headings = document.querySelector('.toc-headings');
headings && headings.addEventListener('click', function(event) {
if (event.target.tagName === 'A') {
document.body.classList.remove('tocActive');
}
}, false);
function createToggler(togglerSelector, targetSelector, className) {
var toggler = document.querySelector(togglerSelector);
var target = document.querySelector(targetSelector);
toggler.onclick = function(event) {
event.preventDefault();
target.classList.toggle(className);
};
}
});
</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/network.md" target="_blank" rel="noreferrer noopener">Edit</a><h1 class="postHeaderTitle">Networking</h1></header><article><div><span><p>Many mobile apps need to load resources from a remote URL. You may want to make a POST request to a REST API, or you may simply need to fetch a chunk of static content from another server.</p>
<h2><a class="anchor" aria-hidden="true" id="using-fetch"></a><a href="#using-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>Using Fetch</h2>
<p>React Native provides the <a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API">Fetch API</a> for your networking needs. Fetch will seem familiar if you have used <code>XMLHttpRequest</code> or other networking APIs before. You may refer to MDN's guide on <a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API/Using_Fetch">Using Fetch</a> for additional information.</p>
<h4><a class="anchor" aria-hidden="true" id="making-requests"></a><a href="#making-requests" 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>Making requests</h4>
<p>In order to fetch content from an arbitrary URL, just pass the URL to fetch:</p>
<pre><code class="hljs css languages- javascript">fetch(<span class="hljs-string">'https://mywebsite.com/mydata.json'</span>);
</code></pre>
<p>Fetch also takes an optional second argument that allows you to customize the HTTP request. You may want to specify additional headers, or make a POST request:</p>
<pre><code class="hljs css languages- javascript">fetch(<span class="hljs-string">'https://mywebsite.com/endpoint/'</span>, {
<span class="hljs-attr">method</span>: <span class="hljs-string">'POST'</span>,
<span class="hljs-attr">headers</span>: {
<span class="hljs-attr">Accept</span>: <span class="hljs-string">'application/json'</span>,
<span class="hljs-string">'Content-Type'</span>: <span class="hljs-string">'application/json'</span>,
},
<span class="hljs-attr">body</span>: <span class="hljs-built_in">JSON</span>.stringify({
<span class="hljs-attr">firstParam</span>: <span class="hljs-string">'yourValue'</span>,
<span class="hljs-attr">secondParam</span>: <span class="hljs-string">'yourOtherValue'</span>,
}),
});
</code></pre>
<p>Take a look at the <a href="https://developer.mozilla.org/en-US/docs/Web/API/Request">Fetch Request docs</a> for a full list of properties.</p>
<h4><a class="anchor" aria-hidden="true" id="handling-the-response"></a><a href="#handling-the-response" 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>Handling the response</h4>
<p>The above examples show how you can make a request. In many cases, you will want to do something with the response.</p>
<p>Networking is an inherently asynchronous operation. Fetch methods will return a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise">Promise</a> that makes it straightforward to write code that works in an asynchronous manner:</p>
<pre><code class="hljs css languages- javascript"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">getMoviesFromApiAsync</span>(<span class="hljs-params"></span>) </span>{
<span class="hljs-keyword">return</span> fetch(<span class="hljs-string">'https://facebook.github.io/react-native/movies.json'</span>)
.then(<span class="hljs-function">(<span class="hljs-params">response</span>) =&gt;</span> response.json())
.then(<span class="hljs-function">(<span class="hljs-params">responseJson</span>) =&gt;</span> {
<span class="hljs-keyword">return</span> responseJson.movies;
})
.catch(<span class="hljs-function">(<span class="hljs-params">error</span>) =&gt;</span> {
<span class="hljs-built_in">console</span>.error(error);
});
}
</code></pre>
<p>You can also use the proposed ES2017 <code>async</code>/<code>await</code> syntax in a React Native app:</p>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">getMoviesFromApi</span>(<span class="hljs-params"></span>) </span>{
<span class="hljs-keyword">try</span> {
<span class="hljs-keyword">let</span> response = <span class="hljs-keyword">await</span> fetch(
<span class="hljs-string">'https://facebook.github.io/react-native/movies.json'</span>
);
<span class="hljs-keyword">let</span> responseJson = <span class="hljs-keyword">await</span> response.json();
<span class="hljs-keyword">return</span> responseJson.movies;
} <span class="hljs-keyword">catch</span> (error) {
<span class="hljs-built_in">console</span>.error(error);
}
}
</code></pre>
<p>Don't forget to catch any errors that may be thrown by <code>fetch</code>, otherwise they will be dropped silently.</p>
<div class="snack-player"><div class="mobile-friendly-snack" style="display: none"><pre><code class="hljs css javascript"><span class="hljs-keyword">import</span> React <span class="hljs-keyword">from</span> <span class="hljs-string">'react'</span>;
<span class="hljs-keyword">import</span> { FlatList, ActivityIndicator, Text, View } <span class="hljs-keyword">from</span> <span class="hljs-string">'react-native'</span>;
<span class="hljs-keyword">export</span> <span class="hljs-keyword">default</span> <span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">FetchExample</span> <span class="hljs-keyword">extends</span> <span class="hljs-title">React</span>.<span class="hljs-title">Component</span> </span>{
<span class="hljs-keyword">constructor</span>(props){
<span class="hljs-keyword">super</span>(props);
<span class="hljs-keyword">this</span>.state ={ <span class="hljs-attr">isLoading</span>: <span class="hljs-literal">true</span>}
}
componentDidMount(){
<span class="hljs-keyword">return</span> fetch(<span class="hljs-string">'https://facebook.github.io/react-native/movies.json'</span>)
.then(<span class="hljs-function">(<span class="hljs-params">response</span>) =&gt;</span> response.json())
.then(<span class="hljs-function">(<span class="hljs-params">responseJson</span>) =&gt;</span> {
<span class="hljs-keyword">this</span>.setState({
<span class="hljs-attr">isLoading</span>: <span class="hljs-literal">false</span>,
<span class="hljs-attr">dataSource</span>: responseJson.movies,
}, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>)</span>{
});
})
.catch(<span class="hljs-function">(<span class="hljs-params">error</span>) =&gt;</span>{
<span class="hljs-built_in">console</span>.error(error);
});
}
render(){
<span class="hljs-keyword">if</span>(<span class="hljs-keyword">this</span>.state.isLoading){
<span class="hljs-keyword">return</span>(
<span class="xml"><span class="hljs-tag">&lt;<span class="hljs-name">View</span> <span class="hljs-attr">style</span>=<span class="hljs-string">{{flex:</span> <span class="hljs-attr">1</span>, <span class="hljs-attr">padding:</span> <span class="hljs-attr">20</span>}}&gt;</span>
<span class="hljs-tag">&lt;<span class="hljs-name">ActivityIndicator</span>/&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">View</span>&gt;</span></span>
)
}
<span class="hljs-keyword">return</span>(
<span class="xml"><span class="hljs-tag">&lt;<span class="hljs-name">View</span> <span class="hljs-attr">style</span>=<span class="hljs-string">{{flex:</span> <span class="hljs-attr">1</span>, <span class="hljs-attr">paddingTop:20</span>}}&gt;</span>
<span class="hljs-tag">&lt;<span class="hljs-name">FlatList</span>
<span class="hljs-attr">data</span>=<span class="hljs-string">{this.state.dataSource}</span>
<span class="hljs-attr">renderItem</span>=<span class="hljs-string">{({item})</span> =&gt;</span> <span class="hljs-tag">&lt;<span class="hljs-name">Text</span>&gt;</span>{item.title}, {item.releaseYear}<span class="hljs-tag">&lt;/<span class="hljs-name">Text</span>&gt;</span>}
keyExtractor={(item, index) =&gt; index}
/&gt;
<span class="hljs-tag">&lt;/<span class="hljs-name">View</span>&gt;</span>
);
}
}
</span></code></pre></div><div class="desktop-friendly-snack" style="margin-top: 15px; margin-bottom: 15px"><div
data-snack-name="Fetch Example"
data-snack-description="Example usage"
data-snack-code="import%20React%20from%20'react'%3B%0Aimport%20%7B%20FlatList%2C%20ActivityIndicator%2C%20Text%2C%20View%20%20%7D%20from%20'react-native'%3B%0A%0Aexport%20default%20class%20FetchExample%20extends%20React.Component%20%7B%0A%0A%20%20constructor(props)%7B%0A%20%20%20%20super(props)%3B%0A%20%20%20%20this.state%20%3D%7B%20isLoading%3A%20true%7D%0A%20%20%7D%0A%0A%20%20componentDidMount()%7B%0A%20%20%20%20return%20fetch('https%3A%2F%2Ffacebook.github.io%2Freact-native%2Fmovies.json')%0A%20%20%20%20%20%20.then((response)%20%3D%3E%20response.json())%0A%20%20%20%20%20%20.then((responseJson)%20%3D%3E%20%7B%0A%0A%20%20%20%20%20%20%20%20this.setState(%7B%0A%20%20%20%20%20%20%20%20%20%20isLoading%3A%20false%2C%0A%20%20%20%20%20%20%20%20%20%20dataSource%3A%20responseJson.movies%2C%0A%20%20%20%20%20%20%20%20%7D%2C%20function()%7B%0A%0A%20%20%20%20%20%20%20%20%7D)%3B%0A%0A%20%20%20%20%20%20%7D)%0A%20%20%20%20%20%20.catch((error)%20%3D%3E%7B%0A%20%20%20%20%20%20%20%20console.error(error)%3B%0A%20%20%20%20%20%20%7D)%3B%0A%20%20%7D%0A%0A%0A%0A%20%20render()%7B%0A%0A%20%20%20%20if(this.state.isLoading)%7B%0A%20%20%20%20%20%20return(%0A%20%20%20%20%20%20%20%20%3CView%20style%3D%7B%7Bflex%3A%201%2C%20padding%3A%2020%7D%7D%3E%0A%20%20%20%20%20%20%20%20%20%20%3CActivityIndicator%2F%3E%0A%20%20%20%20%20%20%20%20%3C%2FView%3E%0A%20%20%20%20%20%20)%0A%20%20%20%20%7D%0A%0A%20%20%20%20return(%0A%20%20%20%20%20%20%3CView%20style%3D%7B%7Bflex%3A%201%2C%20paddingTop%3A20%7D%7D%3E%0A%20%20%20%20%20%20%20%20%3CFlatList%0A%20%20%20%20%20%20%20%20%20%20data%3D%7Bthis.state.dataSource%7D%0A%20%20%20%20%20%20%20%20%20%20renderItem%3D%7B(%7Bitem%7D)%20%3D%3E%20%3CText%3E%7Bitem.title%7D%2C%20%7Bitem.releaseYear%7D%3C%2FText%3E%7D%0A%20%20%20%20%20%20%20%20%20%20keyExtractor%3D%7B(item%2C%20index)%20%3D%3E%20index%7D%0A%20%20%20%20%20%20%20%20%2F%3E%0A%20%20%20%20%20%20%3C%2FView%3E%0A%20%20%20%20)%3B%0A%20%20%7D%0A%7D%0A"
data-snack-platform="ios"
data-snack-preview="true"
data-snack-sdk-version="26.0.0"
style="
overflow: hidden;
background: #fafafa;
border: 1px solid rgba(0,0,0,.16);
border-radius: 4px;
height: 514px;
width: 880px;
"
></div></div></div><blockquote>
<p>By default, iOS will block any request that's not encrypted using SSL. If you need to fetch from a cleartext URL (one that begins with <code>http</code>) you will first need to <a href="/react-native/docs/0.49/integration-with-existing-apps#test-your-integration">add an App Transport Security exception</a>. If you know ahead of time what domains you will need access to, it is more secure to add exceptions just for those domains; if the domains are not known until runtime you can <a href="/react-native/docs/0.49/integration-with-existing-apps#app-transport-security">disable ATS completely</a>. Note however that from January 2017, <a href="https://forums.developer.apple.com/thread/48979">Apple's App Store review will require reasonable justification for disabling ATS</a>. See <a href="https://developer.apple.com/library/ios/documentation/General/Reference/InfoPlistKeyReference/Articles/CocoaKeys.html#//apple_ref/doc/uid/TP40009251-SW33">Apple's documentation</a> for more information.</p>
</blockquote>
<h3><a class="anchor" aria-hidden="true" id="using-other-networking-libraries"></a><a href="#using-other-networking-libraries" 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>Using Other Networking Libraries</h3>
<p>The <a href="https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest">XMLHttpRequest API</a> is built in to React Native. This means that you can use third party libraries such as <a href="https://github.com/niftylettuce/frisbee">frisbee</a> or <a href="https://github.com/mzabriskie/axios">axios</a> that depend on it, or you can use the XMLHttpRequest API directly if you prefer.</p>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">var</span> request = <span class="hljs-keyword">new</span> XMLHttpRequest();
request.onreadystatechange = <span class="hljs-function">(<span class="hljs-params">e</span>) =&gt;</span> {
<span class="hljs-keyword">if</span> (request.readyState !== <span class="hljs-number">4</span>) {
<span class="hljs-keyword">return</span>;
}
<span class="hljs-keyword">if</span> (request.status === <span class="hljs-number">200</span>) {
<span class="hljs-built_in">console</span>.log(<span class="hljs-string">'success'</span>, request.responseText);
} <span class="hljs-keyword">else</span> {
<span class="hljs-built_in">console</span>.warn(<span class="hljs-string">'error'</span>);
}
};
request.open(<span class="hljs-string">'GET'</span>, <span class="hljs-string">'https://mywebsite.com/endpoint/'</span>);
request.send();
</code></pre>
<blockquote>
<p>The security model for XMLHttpRequest is different than on web as there is no concept of <a href="http://en.wikipedia.org/wiki/Cross-origin_resource_sharing">CORS</a> in native apps.</p>
</blockquote>
<h2><a class="anchor" aria-hidden="true" id="websocket-support"></a><a href="#websocket-support" 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>WebSocket Support</h2>
<p>React Native also supports <a href="https://developer.mozilla.org/en-US/docs/Web/API/WebSocket">WebSockets</a>, a protocol which provides full-duplex communication channels over a single TCP connection.</p>
<pre><code class="hljs css languages- javascript"><span class="hljs-keyword">var</span> ws = <span class="hljs-keyword">new</span> WebSocket(<span class="hljs-string">'ws://host.com/path'</span>);
ws.onopen = <span class="hljs-function"><span class="hljs-params">()</span> =&gt;</span> {
<span class="hljs-comment">// connection opened</span>
ws.send(<span class="hljs-string">'something'</span>); <span class="hljs-comment">// send a message</span>
};
ws.onmessage = <span class="hljs-function">(<span class="hljs-params">e</span>) =&gt;</span> {
<span class="hljs-comment">// a message was received</span>
<span class="hljs-built_in">console</span>.log(e.data);
};
ws.onerror = <span class="hljs-function">(<span class="hljs-params">e</span>) =&gt;</span> {
<span class="hljs-comment">// an error occurred</span>
<span class="hljs-built_in">console</span>.log(e.message);
};
ws.onclose = <span class="hljs-function">(<span class="hljs-params">e</span>) =&gt;</span> {
<span class="hljs-comment">// connection closed</span>
<span class="hljs-built_in">console</span>.log(e.code, e.reason);
};
</code></pre>
<h2><a class="anchor" aria-hidden="true" id="high-five"></a><a href="#high-five" 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>High Five!</h2>
<p>If you've gotten here by reading linearly through the tutorial, then you are a pretty impressive human being. Congratulations. Next, you might want to check out <a href="/react-native/docs/0.49/more-resources">all the cool stuff the community does with React Native</a>.</p>
</span></div></article></div><div class="docs-prevnext"><a class="docs-prev button" href="/react-native/docs/0.49/using-a-listview">← Using List Views</a><a class="docs-next button" href="/react-native/docs/0.49/more-resources">More Resources →</a></div></div></div></div><footer class="nav-footer" id="footer"><section class="sitemap"><a href="/react-native/" class="nav-home"><img src="/react-native/img/header_logo.png" alt="React Native" width="66" height="58"/></a><div><h5><a href="/react-native/docs/getting-started.html">Docs</a></h5><a href="/react-native/docs/getting-started.html">Getting Started</a><a href="/react-native/docs/tutorial.html">Tutorial</a><a href="/react-native/docs/components-and-apis.html">Components and APIs</a><a href="/react-native/docs/more-resources.html">More Resources</a></div><div><h5><a href="/react-native/help.html">Community</a></h5><a href="/react-native/showcase.html">Who&#x27;s using React Native?</a><a href="http://stackoverflow.com/questions/tagged/react-native" target="_blank">Stack Overflow</a><a href="https://discuss.reactjs.org" target="_blank">Discussion Forum</a><a href="https://discord.gg/0ZcbPKXt5bZjGY5n">Reactiflux Chat</a></div><div><h5>More</h5><a href="/react-native/blog">Blog</a><a href="https://twitter.com/reactnative" target="_blank">Twitter</a><a href="https://github.com/facebook/react-native" target="_blank">GitHub</a><a href="http://reactjs.org" target="_blank">React</a></div></section><a href="https://code.facebook.com/projects/" target="_blank" class="fbOpenSource"><img src="/react-native/img/oss_logo.png" alt="Facebook Open Source" width="170" height="45"/></a><section class="copyright">Copyright © 2018 Facebook Inc.</section></footer></div><script type="text/javascript" src="https://cdn.jsdelivr.net/docsearch.js/1/docsearch.min.js"></script><script>window.fbAsyncInit = function() {FB.init({appId:'1677033832619985',xfbml:true,version:'v2.7'});};(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/sdk.js';fjs.parentNode.insertBefore(js, fjs);}(document, 'script','facebook-jssdk'));
</script><script>window.twttr=(function(d,s, id){var js,fjs=d.getElementsByTagName(s)[0],t=window.twttr||{};if(d.getElementById(id))return t;js=d.createElement(s);js.id=id;js.src='https://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js, fjs);t._e = [];t.ready = function(f) {t._e.push(f);};return t;}(document, 'script', 'twitter-wjs'));</script><script>
var search = docsearch({
apiKey: '2c98749b4a1e588efec53b2acec13025',
indexName: 'react-native-versions',
inputSelector: '#search_input_react',
algoliaOptions: {"facetFilters":["tags:0.49"],"hitsPerPage":5}
});
</script></body></html>
Reference in New Issue View Git Blame Copy Permalink