<divclass="link title"><ahref="/v5/">Documentation</a></div><divclass="base show link depth-1"><ahref="/v5/getting-started/">Getting Started</a></div><divclass="base show link depth-1"><ahref="/v5/concepts/">Ethereum Basics</a></div><divclass="hide link depth-2"><ahref="/v5/concepts/events/">Events</a></div><divclass="hide link depth-2"><ahref="/v5/concepts/gas/">Gas</a></div><divclass="hide link depth-2"><ahref="/v5/concepts/security/">Security</a></div><divclass="hide link depth-2"><ahref="/v5/concepts/best-practices/">Best Practices</a></div><divclass="base show link depth-1"><ahref="/v5/api-keys/">Provider API Keys</a></div><divclass="base show link depth-1"><ahref="/v5/api/">Application Programming Interface</a></div><divclass="hide link depth-2"><ahref="/v5/api/providers/">Providers</a></div><divclass="hide link depth-3"><ahref="/v5/api/providers/provider/">Provider</a></div><divclass="hide link depth-3"><ahref="/v5/api/providers/jsonrpc-provider/">JsonRpcProvider</a></div><divclass="hide link depth-3"><ahref="/v5/api/providers/api-providers/">API Providers</a></div><divclass="hide link depth-3"><ahref="/v5/api/providers/other/">Other Providers</a></div><divclass="hide link depth-3"><ahref="/v5/api/providers/types/">Types</a></div><divclass="hide link depth-2"><ahref="/v5/api/signer/">Signers</a></div><divclass="hide link depth-2"><ahref="/v5/api/contract/">Contract Interaction</a></div><divclass="hide link depth-3"><ahref="/v5/api/contract/contract/">Contract</a></div><divclass="hide link depth-3"><ahref="/v5/api/contract/contract-factory/">ContractFactory</a></div><divclass="hide link depth-3"><ahref="/v5/api/contract/example/">Example: ERC-20 Contract</a></div><divclass="hide link depth-2"><ahref="/v5/api/utils/">Utilities</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/abi/">Application Binary Interface</a></div><divclass="hide link depth-4"><ahref="/v5/api/utils/abi/coder/">AbiCoder</a></div><divclass="hide link depth-4"><ahref="/v5/api/utils/abi/formats/">ABI Formats</a></div><divclass="hide link depth-4"><ahref="/v5/api/utils/abi/fragments/">Fragments</a></div><divclass="hide link depth-4"><ahref="/v5/api/utils/abi/interface/">Interface</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/address/">Addresses</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/bignumber/">BigNumber</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/bytes/">Byte Manipulation</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/constants/">Constants</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/display-logic/">Display Logic and Input</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/encoding/">Encoding Utilities</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/fixednumber/">FixedNumber</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/hashing/">Hashing Algorithms</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/hdnode/">HD Wallet</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/logger/">Logging</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/properties/">Property Utilities</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/signing-key/">Signing Key</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/strings/">Strings</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/transactions/">Transactions</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/web/">Web Utilities</a></div><divclass="hide link depth-3"><ahref="/v5/api/utils/wordlists/">Wordlists</a></div><divclass="hide link depth-2"><ahref="/v5/api/other/">Other Libraries</a></div><divclass="hide link depth-3"><ahref="/v5/api/other/assembly/">Assembly</a></div><divclass="hide link depth-4"><ahref="/v5/api/other/assembly/dialect/">Ethers ASM Dialect</a></div><divclass="hide link depth-4"><ahref="/v5/api/other/assembly/api/">Utilities</a></div><divclass="hide link depth-4"><ahref="/v5/api/other/assembly/ast/
<aname="cookbook-reactnative"></a><aname="cookbook-reactnative"></a><h1class="show-anchors"><div>React Native (and ilk)<divclass="anchors"><aclass="self"href="/v5/cookbook/react-native/#cookbook-reactnative"></a></div></div></h1><p>The <ahref="https://reactnative.dev">React Native</a> framework has become quite popular and has many popular forks, such as <ahref="https://expo.io">Expo</a>.</p>
<p>React Native is based on <ahref="https://developer.apple.com/documentation/javascriptcore?language=objc">JavaScriptCore</a> (part of WebKit) and does not use Node.js or the common Web and DOM APIs. As such, there are many operations missing that a normal web environment or Node.js instance would provide.</p>
<p>For this reason, there is a <ahref="https://www.npmjs.com/package/@ethersproject/shims">Shims</a> module provided to fill in the holes.</p>
<aname="cookbook-reactnative-shims"></a><aname="cookbook-reactnative--cookbook-reactnative-shims"></a><h2class="show-anchors"><div>Installing<divclass="anchors"><aclass="self"href="/v5/cookbook/react-native/#cookbook-reactnative-shims"></a></div></div></h2><p>To use ethers in React Native, you must either provide shims for the needed missing functionality, or use the ethers.js shim.</p>
<p>It is <b>HIGHLY RECOMMENDED</b> you check out the <ahref="/v5/cookbook/react-native/#cookbook-reactnative-security">security section</a> below for instructions on installing packages which can affect the security of your application.</p>
</div><aname="cookbook-reactnative-security"></a><aname="cookbook-reactnative--cookbook-reactnative-security"></a><h2class="show-anchors"><div>Security<divclass="anchors"><aclass="self"href="/v5/cookbook/react-native/#cookbook-reactnative-security"></a></div></div></h2><p>The React Native environment does not contain a secure random source, which is used when computing random private keys. This could result in private keys that others could possibly guess, allowing funds to be stolen and assets manipulated.</p>
<p>For this reason, it is <b>HIGHLY RECOMMENDED</b> to also install the <ahref="https://www.npmjs.com/package/react-native-get-random-values">React Native get-random-values</a>, which <b>must</b> be included before the shims. If it worked correctly you should not receive any warning in the console regarding missing secure random sources.</p>
<divclass="code-title"><div>Importing with Secure Random Sources</div></div><divclass="code"><spanclass="comment">// Import the crypto getRandomValues shim (**BEFORE** the shims)
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